I'm going to keep this brief, because I know Vic, the bigger Star Trek geek than I, will comment more. Anyway, Captain James T. Kirk will be played by Chris Pine (that's him in the Photoshopped picture as Kirk), who Vic reported was having to make a decision between Kirk in JJ Abrams' Star Trek re-launch, or the 1950s-set crime drama White Jazz with George Clooney.
We now have everyone cast, except Bones, so I'm looking forward to hearing who'll be playing the doctor (and not a _____). Details on Scotty and Sulu casting plus more details, including the villain casting.
Source: Ain't It Cool News