The writer's guide is pretty much the same. I probably wouldn't have bothered posting if I had seen it was online.The links from DigificWriter are to an early draft version of the guide. Is the year 3 version essentially the same thing, just with more up-to-date information, Mr. B?
The TOS guide is 31 pages and the TNG one is 48, both with sections on the Enterprise, its systems, and the technology and procedures used (transporters, tractor beams, communicators, etc.), along with character backgrounds and writing guidelines. The Voyager one looks pretty incomplete in comparison. Maybe Voyager writers were assumed to have general Trek background knowledge already (or were given the "prototype" tech manual as well)?
As for the technical guide, I would imagine alot of writers that came on board to the show had very limited if any knowledge of trek tech based on the language in the guide given to writers. The language used leaves out all the non-canon technobabble in the TNG/DS9 manuals.