Is Borderlands 2 coming to the Mac? It would certainly seem so, given that it's appeared on the Mac-only playlists of anyone who owns the game for the PC on Steam.
As you know, most games (with the exception of the recently released Call of Duty: Black Ops for the Mac) on Steam are available in both Mac and Windows PC varieties for anyone who owns them.
While the game hasn't been officially announced for the Mac or any other platform apart from the PC, PS3 and Xbox 360, Borderlands 2, Randy Pitchford has mentioned over Twitter that the studio does indeed have plans for a Mac port in the near future in addition to the DLCs they're working on.
Further investigation into the CDR on OpenSteamWorks for Borderlands 2 also lists the game as being available on both the Windows and Mac OS X.
validoslist = windows,macos
Could the Mac port for Borderlands 2 be coming sooner than expected? Only time will tell.