I've just put 12mm on my 2011 Team. Only given it 1 quick ride and that was with new wheels aswell but does seem stiffer.
You need-
12mm dropouts
12mm Hope conversion
http://www.chainreactioncycles.com/Models.aspx?ModelID=21849 (end caps and axle for non-evo, Evo just needs endcaps)
135x12mm Bolt thru axle (Superstar prob cheapest)
Theres also the option of using a Maxle instead up bolt thru, which needs specific dropouts.