Yoda Is Your Father said:
If the bloke playing Kirk done a Shatner impression everybody would laugh their arses off and you lot would moan.

Exactly. Hell, I even laugh my ass off when Shatner does it, someone else doing it would be just too much. It is suppose to be a serious movie after all, not a comedy. Simon Pegg as Scotty and the guy from Harold & Kumar as Sulu already has this thing dangerously close to being extremely comedic (wonder why they didn't get Adam Sandler or Jim Carrey to play Bones?), you really want to see Pine running around making a lousy attempt at imitating Shatner?