Valve would be cool. Rare isn't the company it was anymore and it would lead to M$ exclusivity.
Crytec UK would be the best choice if EA buys the rights again.
But right now, it's only speculation that AB will give up the rights, because the only thing that happened is that the games were removed from the market places.
Far more interresting would be to know what will happen to all the ppl who allready have the games and wanna download them or DLC (Like the skyfall mission in 007 Legends) again, or even play on a multiplayer server.
But even if they lose the licence now, i don't see a reason to remove games they released when they had the licence.