The Steam edition of Battlefield: Bad Company 2 will ditch SecuROM in an upcoming game patch. Valve's own authentication service will be used instead.
The update, version 522175, is imminent. Apparently there's a bit of extra QA on Steam to bypass.
All non-Steam users can download the patch now. Unfortunately, a few problems appear to have cropped up; members of the BFBC2 forum report crashes to desktop after installing the update, and some are having account login issues.
There's a full list of changes on the Battlefield: Bad Company 2 forum.