Pawlenty would probably be a net negative in Minnesota and completely irrelevant in the other 49 states. IMO, Pawlenty is probably one of the worst picks Romney could make. Then again, the word is that Team Romney is looking for the most unoffensive, boring white man they can find; Tim Pawlenty is unparalleled in the arts of being a relentlessly generic space filler.
this
I kind of agree with this, too. My take is that Romney himself is kind of charismatically-challenged, so the last thing he wants is a VP who upstages him. Pawlenty would do a good job of not upstaging Romney.
He also has working-class roots, which might help neutralize some of the attacks on Romney.