From Boomtown.dk:
Bad Company 2 maybe for Mac
DICE does not preclude a Bad Company 2.dmg is underway.
This week we Boomtown until further written much more news about gaming on the Mac than we usually do.
This is obviously because the game service Steam is coming to Apple Computer, and Valve is not the only ones who want to expand the catalog of games platform.
Karl Magnus Troedsson from DICE is also very positive about Steam client for Mac, and do not reject that Bad Company 2 coming to Mac OS X:
"We're currently investigating the possibility of making BFBC2 available on the Mac." <<<<<<<<<<<<<<
It has recently been published that Steam in April will have a client ready for the Mac, while Valve will also publish a plethora of titles for their platform.
Battlefield: Bad Company 2 came out last Thursday for PC, PlayStation 3 and Xbox 360
Source: Joystiq