Manee WAG, great to have someone else to talk to in here (it seems that the nefarious Diet Coke drinking Liverpudlian has better things to do than to talk about these serious matters).
I predict the following:
1) Rock will defeat Cena, possibly leading to some sort of Cena heel turn, with possible involvement from the shield. Apparently Rock is signed up for another 12 months of appearances, so I anticipate he will walk out the winner here, and probably drop the title in a rematch with Cena at the next PPV, surely Cena winning would be too predictable. In any case, this won't be the last we hear of this feud, I suspect.
2) HHH will beat Lesnar imo. Brock's return has on the whole been pretty disappointing (should have put him in a match with Punk for mine), and can't see him going over HHH twice.
3) Taker will beat Punk, perhaps not a bold prediction, but if Punk wins this one I'll spit nails. Should be a top match this one.
I've not followed enough to really have much to say about the other matches, but the Jericho one has the whole "Jericho putting over a young up and comer" written all over it.