Mike Pence has actually announced he isn't running, period. DeMint has said no, and recently a few here have championed his not closing it out entirely when he said "it would be the last thing in the world he would want". It's just seriously unlikely (I personally wouldn't mind him running at all).
And no, we don't know who's running, other than Romney, and Pawlenty are in. Huckabee is a probable, Sarah Palin seems to be as well.
There are names bandied about here that are unrealistic, such as Hunter and Bachmann plus a few others who are congressmen, and that's just unrealistic and la la land thinking. No congressman is going to get close to the nomination, it hasn't happened in over a century for good reason.
A couple of potential darkhorses, but the likelihood imho is it will come down to either Romney or Palin.
"... the likelihood imho is it will come down to either Romney or Palin."
I am not buying that. This far ahead of the 2008 elections Giuliani looked like a shoe-in. There was a point where it looked like it would come down to a race between Giuliani and Thompson. Both suddenly collapsed. After the 2010 elections are over the picture will be more clear and I will have a better idea of who to support. That person ideally would be someone who stood up to the GOP led spending spree as well as opposing Obama and the Dems. The person could be a current Governor, it is just too early to tell. If the race ends up being between Mitt and Sarah, I will cross that bridge when I come to it. Right now I am not very enthusiastic about the current crop of "likely" candidates, which does not concern me as my focus is more on 2010.