By the way, since we're talking about Daggerfall merchandise, does anyone have the Daggerfall Chronicles? How is it? I've considered more than once to buy it but now with the UESP offering all the information about the game, I don't think it's necessary.
Daggerfall Chronicles was a great guide for its time, and there's some good information that's still not on UESP. I bought my copy way back in 1997--by now a lot of the pages have fallen out, and the ones that remain are covered with my own handwritten notes. It's quite a sight. I would have NEVER found my way thought the main quest without it. Back then, the UESP was fairly new, and the only source for good information was the guidebook or the Bethesda BBS. (And a host of old fansites that seem to have long since fallen by the wayside.)
Is it still useful in 2009? Not really. But it's a cool Elder Scrolls artifact. What I liked most about it was there was an effort to provide a little bit of extra lore for every quest, and there are still some tidbits of information that I think only appear in the Daggerfall Chronicles (though I hear much of it has since been retconned.) There was actually a family tree of the royal families of all three kingdoms, a rundown of the game's backstory, a timeline for all three eras of Tamriel's history, a sizable description of every major artifact, a great bestiary, and a lot of other goodies. Like Jormungandr's review says, it also seems to have been written before the game was finished, so it's another good source for frustrating information about the Daggerfall that could've been.
So I can't recommend it as actually being useful for playing the game in the age of the UESP. It does, however, go well beyond the level of information in most game guides. Basically, if you only buy one printed ES guidebook, Daggerfall Chronicles is the one to get.