Well right here we completely and severly disagree. For me these characters ARE NOT INTERCHANGEABLE like batman/superman/bond/spiderman...there's only one Kirk period amen. When anyone mentions star trek...me and everybody i've ever known thinks of one thing: TOS...not next gen, not deep space etc..etc..etc...
So with star treks more recent series; they've tried to capture the original magic but it's never really lived up to it....don't get me wrong the newer star treks are not bad -- but they can't come close to TOS...I'm sure people will wanna rip me a new one over that comment so i better just lube up right now. LOL
No offense, that just sounds like the position of a hardcore TOS fan and not of the general Trek fan or even the mainstream public. Recasting and reboots have worked for other franchises, so I don't think that in particular will be a detriment to this movie.
I'm not sure a movie could be made that you would be happy with, if that is your stance. The original cast won't be reuniting. Hell, they can't, since two of them are dead.