I honestly think that at the rate Pacquiao has been improving, he'd knock Marquez out in under 6 rounds.
I'd love to see him fight Floyd, and honestly I don't know how well even Floyd's vaunted defense will hold up.
You can train all you want, but its nearly impossible for any other fighter to replicate what Manny does in the ring. He throws punches from awkward angles, and he throws them in bunches.
His unorthodox style coupled with his blazing speed and accuracy are a matchup nightmare for anyone.