People,
It's true that the reboot (sorry, Beaker, I have no problem using it, so I have no stake in "officially" retiring the word), or reimagining, or updating, or whatever phrase you choose to use, falls into territory seldom traveled by fictional characters. You can count on one hand the number of familiar characters who've been recast after another actor made the role famous -- think Sean Connery and James Bond, for example.
However, TOS's characters first appeared on TV. So making a comparison to those characters being recast versus how characters who first appeared in another medium -- novels or comics -- who were then recast, isn't quite apt. But just for the sake of argument, those characters survived such recastings. I'm thinking of Superman, Batman, Tarzan, the Phantom, Buck Rogers, and Flash Gordon, just to name a few.
For the most part, I actually like the actors they picked, although the only one I'm having a hard time accepting is Chris Pine as Kirk. I think the best choices are Zachary Quinto as Spock and Karl Urban as McCoy. Both look enough like their predecessors but also have their own look that they're successful recastings, IMO.
I am looking forward to seeing this movie. Part of the fun is comparing the new version to the original, in all candor.
Red Ranger