Until I tried it in landscape mode, which slams the framerate so hard I can't get ANY sprites on screen at 60fps.
Give it a try - load it up on a new ipad and switch between portrait and landscape modes and watch the difference.
It happens in another game I'm making too. Any idea why this happens?
Here's the .capx if you want it: http://www.amirai.net/ipad/sprites/ipadfps.zip