They definately have several more months as a trio, and it's already reported they'll win the tag team championship soon.
But after their tag team title reign I predict they'll break up.
Seth Rollins will go on to be the mid-card babyface, and probably spend most of his career at the IC / US title level like Kofi Kingston.
Dean Ambrose will probably be the career heel, and have a Jericho-like run: permenantly in the upper-card, but never a full main-eventer.
Roman Reigns is definately the one with the most main-event potential. He's got the massive frame and threatening look, but he dosen't look like a roid monster that can barely talk (Ryback, anyone?).