Some consider this to be the ho-hum followup to a great show. I couldn't disagree more.
Aside from the fact that it's a cartoon and the episodes are rushed in 30 mins, I found this to be a philosophical cut above the Trek of the late 60s. Here in the animated series, we catch a glimpse of some amazingly progressive ideas such as non-violence, compassion and tolerance. Kirk & Spock aren't so quick to set phasers on kill as they were before. Klingon/Federation confrontations in space are resolved without bloodshed. In one episode (my favourite), Kirk defends Lucifer's right to live, because Lucifer--for all his past crimes and flaws--is a living entity. Folks, this is some advanced stuff.
Of course that means we don't see as much "action". Not many shootouts. Nothing violent really. The red shirts don't get wasted as bad. You may find yourself screaming at the TV, "Kirk, you WUSS! I woulda KICKED HIS ASS!" But that, I believe, is the whole point of Gene Roddenberry's visionary creation--that humans of the future would be a much more evolved, diplomatic and nonviolent species. This was evident in the original '66-'69 Trek, but we get it full force in the '74-'75 animated series.
If it means anything to you, both William Shatner and Leonard Nimoy were vegetarians for ethical reasons during the production of this show, and they still are today. (Edit 7 years after my original post: I'm pretty sure William Shatner has been poundin down the pepperoni pizzas lately, but Nimoy is still a veggie)
So if you're looking for zap-zap, kill the monster, good vs. evil stuff, you'll be disappointed. If instead you're ready for a truly philosophical mind trip, bordering on Buddhist spiritualism, then this will rock your socks.
And the music is primo.
9/10.
