No Zack & Wicky votes yet? Although Mario Galaxy is my most wanted and Z&W close second, I'll choose the Treasure Island Z miracle. I love games, which are original, new, like something you haven't seen before, therefore I personally like Dewy so much ;)
Edit: After reading all the posts I see, I've got 3 fellow voters :D
PLAYSTATION®3 is the future.....NOW.......B_E_L_I_E_V_E
Supporter of PlayStation and Nintendo