You are correct. Gavin Norman made B/X Essentials then decided to make it better with Old School Essentials and dropped the B/X Essentials brand
You can always ask Gavin Norman (The creator of OSE and Necrotic Gnome) on his twitter @NecroticGnome of on the OSE Facebook group for confirmation.

I've been collecting OSE for the past couple years and the releases can be confusing.
First thing to understand is there are two rule groups The Classic Fantasy and the new Advanced Fantasy.

The Classic Fantasy is the initial releases. It's B/X D&D cleaned up and reformatted.
- a box set with 5 smaller Classic Fantasy books:
----Core Rules (note: Core Rules are the same in Classic and Advanced- they are 'Core' )
----Classic Fantasy Genre Rules
----Classic Fantasy Cleric and Magic-User Spells
----Classic Fantasy Monsters
----Classic Fantasy Treasures

- A Classic Fantasy 'Rules Tome' that contained all 5 of the smaller books in to one book. Like a Dungeon Master's Guide and Player's Handbook all in one.

- Later came a Classic Fantasy 'Player's Rule Tome' that only contained the Player facing rules from 3 of the smaller books: Core Rules, Classic Fantasy Genre Rules, and Cleric and Magic-User Spells.

Then Advanced Fantasy Rules were released: This is material from Advanced Dungeons & Dragons first edition - modified to be more like B/X D&D instead of AD&D 1E
- 4 smaller Advanced Fantasy books:
----Advanced Fantasy Genre Rules
----Advanced Fantasy Druid and Illusionist Spells
----Advanced Fantasy Monsters
----Advanced Fantasy Treasure

This is where is get's the most confusing:
- An Advanced Fantasy Referee's Tome that contains all the Referee facing rules from BOTH Classic and Advanced Fantasy Rules that a dungeon master would need: The Core rules a referee would need; Classic and Advanced Genre Rules a referee would need; Classic and Advanced Monsters; Classic and Advanced Treasures.

- An Advanced Fantasy Player's Tome that contains all the Player facing rules from BOTH Classic and Advanced Fantasy Rules: The Core rules a player would need; Classic and Advanced Genre Rules a player wold need; Cleric and Magic User Spells; Druid and Illusionist spells

In short if you want the all the rules for both Classic Fantasy and Advanced Fantasy then buy the Advanced Fantasy Referee's Tome and Advanced Fantasy Player's Tome.

Note: Technically the first printing of 'Advanced Fantasy Genre Rules' and 'Advanced Fantasy Druid and Illusionist Spells' books came out the same time as Classic Fantasy and they both were reprinted as second printings when the Advanced Fanstasy Kickstarter released.

Let me know if you have any other questions.

mbassoc2003 wrote in OSR question:Some of that looks like republishing books as new products for the sake of trying to stay in the public consciousness and to create revenue.

Ok.

Edit: i have just bought a full set of b/x books... Collecting-wise these are supposed to be the most difficult to find as they are oop, right? Any idea if they are collectable?

I cannot talk to Necrotic Gnome products specifically, but I think the proliferation of high quality PDFs originating from OSR publishers themselves will dramatically cut the investing pool of collectors in the future.

I also think that the numerous differing sources for Print on Demand used by publishers and electronic resellers, used by many OSR publishers, mean that there are many different hardcopy printings of any one PDF. So if we have Fantastic Book of Magic and the flyleaf says if Version 1, there could be the PoD version printed by the publisher themselves to fulfil Kickstarter orders, and there could be PoD versions printed for customers who buy from Lulu, and others printed by another source printed by whoever OneBookShelf use.

So unless there is something unique about the physical entities in the Kickstarters, that are not reproduced in the distributed PDFs, I don't see any real value in physical hardcopy the way we see value in the collectables generally collected by many on Acaeum.

Also, given the ease with which stuff can now be published, the volume of product that can be collected is massive, and increases in the rate at which it is being published (electronically at least) every year. So whilst fewer physical copies are being printed by publishers, the means of publishing as and when desired is being handed directly to the buyer of the PDF (and anyone else who downloads those PDFs online). They simply send the PDF to a publisher and wait for their copy to arrive in the post.

Going forward I don't see how you track genuine publisher distributed hardcopies from other print-on-demand copies.

For example, if I buy a hardcopy of a book from Necoritc Gnome's listing for their book on DrivetruRPG the week it is published, is that a genuine copy? Does that have any collectable value? Is it any more or less valuable that a copy Necrotic Gnome sent my friend the same week because he had backed the Kickstarter? Can the be distinguished between one another? Potentially they may have both been printed at the same PoD printer. If I send the PDF I get for backing a Kickstarter at a low level to a PoD publisher ten years from now, have I just created a 10 year old Kickstarter original if the PoD publisher doesn't add their own date and printer mark anywhere?

Is the value going forward going to be solely in the free bookmarks, condition of the box, poster map, ephemera, because the books have nominal collectable value only?

There is phenomenal quality in what the OSR has created in the past decade, but with few exceptions, I see most of it in 20 years time being as easily obtainable and of no more value that your average copy of B2 Keep on the Borderlands today. In some cases the exceptions to that rule are distinctive print runs (Swordfish Islands for example using partial leather bindings and foil embossing on the covers), or those publishers who do not publish in PDF at all, and leave the market to scan and create their own PDFs which (for the time being) destroys the possibility of after market printing of any discernable quality. With Weird on the Waves for example, the author released a low quality PDF only in order to limit physical reproduction. Sadly it also seems to have limited sales.

It's certainly interesting to watch the OSR space developing. The majority of the money I now spend on the hobby is now being spent in this space. But I am not doing it with a view to collectability, because for the most part I do not see the future of collectables here in the sense that we have come to think of it on Acaeum.

It pretty much looks like we have similar views on the future collectibility of modern printed OSR stuff.

In regard to KS exclusive premium quality printing, in whatever forms those take, I think this is a must for those who want to invest in a collectible and not just buy a product to play with. If this becomes a learned process and established as the norm in the OSR publishing community, I think we will see more investment from collectors, and more work actually reaching print from some of our more talented authors and artists.

Of course, you’ll always get those half arsed publishers who just don’t understand presentation and quality, those who are out for a quick money grab, and those who are inherently dishonest and just out to fleece the gullible. But at least there is a chance to move the focus from the outset onto quality and presentation. It would be good to get to a stage where the focuses at least someone in a prospective KS team was on presentation and quality from the outset, and this would help to establishes the PDF as a distinctly second rate product. That is a distinction that I think is important if the OSR is to survive, because at the moment there is very little return in exchange for time invested by the author.

Most of the return authors get at the moment in the OSR space is not monetary.

Whilst PDF sales are an immediate hit of funds and a constant drip of regular income, they on the whole reach the free download market within a couple of days of public release. So for some people these PDFs are free, and always will be, right from the get-go. For others they are discovered some months down the line, as proliferation spreads the files across the web, and in many instances that includes ‘KS exclusive content’, ‘Kickstarter exclusive scenarios’, Kickstarter only artwork’ etc., as KS Exclusive content is still created digitally and distributed to printers, and those files exist one way or another on people’s harddrives, Dropbox folders, cloud storage, e-mail histories etc. Nine times out of ten someone trusted in the chain of custody is not trustworthy.

Recently (maybe 6 or 9 months ago) it was announced that a new venture was going to publish adventures from the legendary authors of our hobby. First up I think was Return to the Living Room by RJK. The PDF was being freely distributed the same week the advert was in the classifieds. I wonder if they ever published anything else, or if they threw in the towel in the face of the modern realities of digital publication versus monetary returns.

For my part I buy selective PDFs from authors I have I have come to like, and I take cues from YouTube reviews like Questing Beast and others. If I like what I see and believe it’s going to increase in value over time, I hunt down the original premium publications. If I just want to read something, I stick with the PDF. I ignore everything else.

I am occasionally tempted by a particularly well branded dice bag or a deck of cards with a useful game mechanic, but those things are rare. The OSR space is my primary focus, although I am always in the market for the odd unpublished manuscript or stupidly rare book that hasn’t passed through my hands in the past.