My thoughts on the main cards:
1) Jardine vs. Silva: This is a hard one. Both are good strikers, with Jardine being the more patient one and better game plan, and Silva being the wild swinging one and lots of aggression. I think the rules of the UFC (no foot stomps and soccer kicks) took a lot out of Silva, like it did to Shogun. From the last fight with Liddell, I think Silva still got it. But then Jardine would want to win this to prove that he should be the next one in line for the title, not Forrest. I think it would be a good match, and it will be a TKO/KO. I hope Silva can end his 4 match losing streak and get a TKO in the second round.
2) Machida vs. Ortiz: Lyoto Machida is my favourite light heavyweight. I know he may be boring to watch, but he is so technically skilled and methodical. He's a true athlete of the MMA sport. However, I think he may have trouble with a wrestler and a ground and pound guy like Ortiz. Ortiz hasn't done much in the last few years, but he could still take people down. As far as I remember, Machida is a black belt in BJJ and Shotokan Karate, but does not have great wrestling skills (but he's won Sumo tournaments before, so I don't know if that will translate). If Ortiz comes out with lots of fire, especially towards Dana White and the UFC, he will be active in the GnP, and he could get a decision. I've seen Machida against stronger opponents like Sam Greco, and he did not look too impressive. Still I believe Machida will most likely be prepared for Ortiz, and get a TKO in the second round or a unanimous decision.
3) Penn vs. Sherk: BJ Penn is probably the most skilled and well-rounded fighter not named Fedor Emelianenko. I haven't see many of Sherk's fight, but I don't think he would fare well against a great BJJ specialist like Penn. With Penn's much improved conditioning, as seen in his fights against Pulver and Stevenson, he would not have much to worry past the third round (if it goes that far). Sherk may take him down occasionally, but Penn would neutralize his GnP and takedowns with his BJJ skills and much improved boxing. I see Penn keeping the title with a second round TKO or submission by rear naked choke or triangle choke (maybe even the mythical gogoplata?)
To chime in on the GSP vs. Anderson Silva fight. As much as I would like to take GSP for the win, Anderson Silva would most likely demolish him in the standup. The Spider has a much better reach advantage and could keep GSP away with strikes. Even on his back, Silva is a BJJ blackbelt and has some sick upkicks (e.g. the fight and "loss" against Okami). The only way GSP could win is to grind out a 3 round decision win with takedown attempts. Now, I would like to see Silva fight Roy Jones Jr., even though I think Roy Jones Jr. would win under boxing rules.
What do you guys think of my predictions?