Originally Posted by
ChrisIII
The Star trek expanded universe stuff has never really been canon (Although, like with Star Wars, some of the stuff from them-mostly names-has been incorporated here and there into the canon). However, I think that mainly started as a Roddenberry thing before becoming official policy, and he didn't consider any Trek he was only partially involved with (Such as the cartoon series and the films after TMP, especially V and VI, although in the former who can blame him) to be canon.
Granted, some of the Trek EU has gone on some weird tangents. The Gold Key comics didn't really get the characters or the series concept at all, and the DC comics, while much more fun and far better well-written, have a ton of continuity issues with the movies.