AT&T - Rollover Data?

This is extremely third-hand and I'm not sure I believe it, so I figured I'd post what I've heard here and see if anyone can corroborate.

A co-worker is on assignment with AT&T, and this co-worker said AT&T is planning on updating their Mobile Share plans to include rollover data. The back-end systems are in place to support it, but the timing is a marketing issue they haven't figured out yet.

Maybe it never sees the light of day, but if it's true, it would be a sign they are looking to remain competitive against the other carriers as their LTE build-outs progress into 2014.

I personally don't believe it to be true, although I would really like for it to be.