Good point
Ultrabook is not a marketing name attached to the Atom line of CPUs by Intel. It's attached to the CULV variants of the sandy bridge processor line. But don't worry... Ivy Bridge is coming too.
I don't want to sound like a spoil sport, but Ultrabooks can include high end graphics adapters, but they DO include the HD 3000 with 12 EUs. I won't say they compare to the GT540M in my notebook, but most games I play, I just run on the HD 3000 on this machine since it has a respectable frame rate.
So, while I'm sure you'd love to start a war between Intel/AMD or Intel/ARM, frankly, the Ultrabooks are not what you think. They are instead, netbooks with high end processors.
I personally would love one if they'd do two things...
1) Stop calling them Ultrabooks that's the dumbest name I've ever heard and I feel like I should pretend to be PeeWee Herman hitting on a girl at the library telling her about my Ultrabook.
2) Make it a requirement that ultrabooks contain reversible multitouch screens. iPad kinda sucks... tablet PCs are pretty lame. But a really thin notebook which can be used as a tablet actually sounds pretty nice.