Chris Christie seems to be generating more and more buzz, though there's no way he's going to run in 2012, so maybe 2016? Of course, it depend on whether he's able to win reelection or not, and whether he wants to potentially cut his second term short for the presidency. He's young enough that waiting until 2020 is a viable option.
His approval ratings are in the toilet and it would take a miracle for him to win reelection at this point. He would make a fine president, but, sadly, he can't win after being a one-term Governor.
Uh, his last job approval number was 45%, no?:
linkAnd there are still three years to go before he faces reelection. Many many governors have rebounded from worse approval numbers than that. Governors across the country are unpopular right now, because of the economy. That isn't necessarily still going to be the case in 2013.
And I wouldn't rule out the possibility of him going the Romney route and stepping down after one term to run for prez in 2016. I don't think GOP primary voters are going to punish him for that. Romney paid no price for doing that in 2008. He lost the nomination to McCain for reasons that were unrelated to his stepping down after one term.