What game do you think will be more successful, Bioshock 2 or Mass Effect 2?

Bioshock 2 as it's on more platforms (PS3 in particular).. ME2 being a RPG will be awesome, but frankly most western gamers are FPS oriented and RPGs really get the short hand of the stick. For example, ME2 sold less than 2 million units on the 360 and sold less than 3 million overall (360+PC). I loved ME2, but still when you have a game on more than 2 platforms, you expect a AAA title to sell more.

Either ways, I am gonna get both when they come out (ME2 on PC due to better graphics and Bioshock 2 on PS3 or 360), both seem awesome.