PC Gamer has discovered that Steam Keys can be used with certain Electronic Arts games to have them essentially “taken over” by Origin. Inputting the keys for Battlefield: Bad Company 2, Dragon Age: Origins, Mass Effect 2, Dead Space 2, Alice: Madness Returns and Dragon Age 2 will allow the user to redownload the games via EA’s proprietary service.
It was observed that you can also use Origin to open existing Steam versions of some games. For instance, Origin can open the Steam version of Dragon Age 2, complete with full Steam functionality. Not all of the keys work, either. Mass Effect’s, for example, cannot run in Origin.
That’s interesting. Not by a huge amount, but it’s a “thing” nonetheless.
EA Steam keys can be activated on Origin [PC Gamer]