I just dug out the book and looked through it briefly. It's pretty much as everyone described it. The production items to me are the most interesting. The stills seem to mostly be ones which have been published before.
The bulk of the book is the episode synopses,which, in leafing through quickly, I remember as being extremely detailed.
And one source of episode synopses which I don't see mentioned here are the ones which make up Kathy Resch's Concordances. I find those very useful, though in some cases they were done before even tapes were avaliable, so there are glitches. However, the additional articles (esp. the Warren Oddson one in the 1840 edition, covering the time travel non sequiturs with Angelique) and illustrations (fan art-- who remembers it?) make those my favorite sources.
Jeannie