Although it exists and been publicly demo'd, the Atmos version of Sgt Pepper has not been publicly released (which is a damn shame). I own the expensive Sgt Pepper box set with the Blu-ray with DTS-HD MA 5.1 and Dolby True HD 5.1 but no Atmos. I wish they would release the Atmos mix on Blu-ray without having to buy another expensive box set again.There's some pretty good albums released on ATMOS. A few that come to mind:
Beatles: Sgt Pepper
REM: Automatic For The People
Max Cooper: Emergence
Booka Shade: Galvany Street
Abbey Road was released in Atmos and sounds great on my system.