Fail plan on a release to production with differential backup
You can't use differentials as stated in the other answer, but you CAN use database snapshots. They require Enterprise Edition, but they function exactly like what you're looking for. You take the snapshot, start your deployment, do user acceptance testing, and then either delete the snapshot or roll back to it.

Be aware that "snapshots" is an overloaded term - there's also snapshot replication (which wouldn't help) and SAN snapshots (which actually would help, but it requires a SAN, which I'm guessing you don't have.)