It's always fun to listen to Republican pundits after a week or more of Democratic talking heads providing their VP and DNC spin.
Ben Domenech (founder of RedState—a great GOP read) chimes in on his own site to offer some stellar John McCain vice presidential speculation:
Biden slightly hurts the rationale for Romney. I do think that Romney would've been a bad choice from the get-go, and very out of character for McCain, but this makes it even less appealing, because Romney eliminates a good 2/3rds of the attacks that can be launched on Obama-Biden - on flip flops, on using quotes from debates against each other, on the economy. Romney's chief attributes shine when he sounds like a technocrat - but Biden is going to go populist in response, and I doubt Romney is an astute enough debater (he certainly didn't show it in the primary) to avoid getting tripped up and coming off as out of touch, wealthy, etc.
Blue collar executive experience = good.
White collar executive experience = bad.
Well put, Mr. Domenech.