Back to the St-Pierre/Silva topic, I would definitely choose Silva to win if I had to choose, but it's not like St-Pierre doesn't have some important tools that could make it a competitive fight.
St-Pierre is cautious overall, certainly, but it's not like he doesn't attack. His brand of caution isn't like Leites vs Silva caution, or even Maia vs Silva caution. **** will happen, and I would hope St-Pierre would be at least somewhat successful.
I think Silva would also have a much harder time drawing St-Pierre into a sparring match, which is where Silva really excels. When Silva is heavily attacked, especially with wrestling, his defenses and counter-punching start to crumble... We've seen that with Sonnen twice, against Henderson, Lutter, Takase, Luiz Azeredo, and Carlos Newton. So I think St-Pierre could easily be successful with his wrestling, and given his ability to compose himself under pressure, I think it's a real possibility for him to find a winning rhythm. Of course, it would probably be a mostly-boring decision, but at least it could finally be proven that Silva isn't a superman or anything.
If it did go to the ground, I think Silva would have a much harder time getting out from underneath that wrestling half-guard smash than he did against Lutter or Henderson. Even though Lutter is an amazing grappler, I'd still argue that GSP's MMA-functional wrestling is much more tuned to the sport he is playing than other wrestlers or grapplers. His base is fantastic.