F1: Drivers - Kobayashi

(not really) I think Vettel will make a strong challenge for the title this year unless Schumacher is still competitive at the age of 41.
Constructors - As much as I hate to say this, I think McLaren or Ferrari could have a good shot at the title unless there is too much inter-team fighting (e.g. Alonso & Hamilton in 2007).
V8 Supercars: Even though Triple 8 is switching from Ford to Holden

I expect Whincup to win his third title in a row. However, I also expect Will Davison to challenge Whincup.
Teams - Going to be close between 888 & HRT this year. The best of the rest I think will be DJR and GRM.
NASCAR: Carl Edwards is overdue for a championship win, but Jimmie Johnson will be hard to beat.
Le Mans: Peugeot looks to be the strongest team, but you can never count out Audi. Aston Martin could surprise this year while Pescarolo will probably be the strongest privateer team.
DTM: I expect Timo Schieder, Gary Paffett and Mattias Ekstrom to battle for the championship.
FIA GT: GT1 - The Vitaphone Maserati and the Corvette team (I can't think of their name) will be the contenders this season
GT2: Bruni & Vilander in the A.F Corsa Ferrari and Westbrook & Collard in the Prospeed Porsche will battle for the title this year, just as they did in '09
GT3: Jean-Denis Deletraz

(not) The Hexis Aston Martin team will be hard to beat this season.
BTCC: Plato in the Lacetti and Turkington are my top two picks, but Giovanardi and Neal could be title contenders without the Vauxhall backing. Tom Chilton could surprise in the Focus after his pole position at Brands Hatch.
WRC: Loeb will be hard to beat as usual, but I hope Hirvonen can beat him for the title. Sordo, however, is the Rubens Barrichello of WRC, as he is the second driver who is there to back up his team-mate.
MotoGP: Stoner, Rossi, Lorenzo and Pedrosa will be the title contenders, but could Ben Spies challenge the top four or will he be just like all the other WSBK champions who come to MotoGP.
WSBK: I think Haga will be hard to beat this year.