Well... remember when we went to the movies? [You know, their first date. Almost three weeks ago.] It's pretty much for the same reasons — the way they portray basic human nature, the mix between the fantastical and the logical... not many realize this, but Star Trek was actually fairly technologically accurate, especially for that time.
[And those are all good reasons. Good, accurate reasons. A nice, neat little list of why something can be considered good or interesting or fun. But... when it comes down to it, that's not the real reason why he liked it. Likes it.
If anyone deserves to hear the right reason, it's Kitty.]