In a word - sh!te.
At least to original campaign material had that nostalgic ring of authenticity and age about it. Even if it wasn't as good as some of the other JG product that came out. But the constand rehashing and reselling of Blackmoor has produced product that can only really be compared to Worlds Largest Dungeon in terms of quality. Too thin to hold a door open with, so unless your table has a leg 1/2" too short, you're better off taking the covers off and hanging it on a nail in the cludgy.

When he died, I was trying to figure out what's out there of Blackmoor.
So far, this is what I came up with.  What's missing and what reviews would people give them?

Supplement II - Blackmoor (0E), TSR, 1975
DA1, DA2, DA3, DA4 (Ex), 1986-7

First Fantasy Campaign (?), JG, 1977

Dave Arneson's Blackmoor (3.5E), Goodman/Zeitgeist, 2004
The Wizard's Cabal
The Redwood Scar
Player's Guide to Blackmoor
Temple of the Frog

Dave Arneson's Blackmoor (4E), WOTC, 2008
Dungeons of Castle Blackmoor (3.5)

I didn't mind the work on The Dungeons of Castle Blackmoor.

Arneson included the dungeon maps in First Fantasy Campaign but notes that he had long-ago misplaced the room descriptions.  I haven't cross-checked the two publications, but the maps in the D20 product at least look similar in style.

Zeitgeist Games strikes me as ill-equipped to be a D20 publisher since they seem more focused on computer gaming.  A production glitch on The Dungeons of Castle Blackmoor renders a pretty nice color painting as essentially a dark brown blotch with a small glowing sword visible in the lower center.

Certainly, Arneson's web presence for Blackmoor seemed to be far more interested in promoting the setting as a MMORPG.  I always had the impression that the D20 books were seen as vehicles for that larger goal.

Arneson is listed in the credits as "lead designer."  One has the feeling that the writing team of Dustin Clingman et al did most of the actual creative work.  Clingman is also listed as the executive producer.  Something makes me suspect that Arneson did little more than nod OK when they showed him the proofs.  All in all, that might be a good thing.

That said, I do like the publication, even if it isn't mapped well for the 3rd Edition rules.  (10' squares are very old-school, but the DM will have to redraw everything for the 5' squares and movement rules of 3rd Edition.)   At lot of this dungeon is well thought out and there are mapping twists, plot devices, unexpected events and the like that old-school players used to just love.

For the cover price of $40, this book is a middling to low value. But, certainly, Mongoose has sold less for more and other game companies have offered less useful text for more bucks.

The Blackmoor name keeps prices high on Ebay.  I keep hoping people will dump this set, allowing me to find it for its actual value.  Now that we've discussed it here on the Acaeum, that wait is gonna be longer.  

Now, wait a minute here: is it "shit" or "shite"? You mention both ...  

'Shite' is a very Scottish word. I don't know how much it's used around the world.  

Yeah. Fek is an Irish thing.
Although it could be Shrek's little sister.

No it's just fecking shite  

wees shud al waash oor gobs oot wi sape an watter

(ulster-scots)