Can it run Crysis? Most certainly not! But through online game streaming service Otoy (similar to OnLive or Gaikai) running on the iPad, it can play it.
Check out the video below posted by TechCrunch.
Of course, the streaming technology makes it possible to play anything on the iPad, as the hardware only has to deal with input and output over a fast internet connection.
If these services take off, almost anything with a good connection will be able to "play" Crysis. Can't say much about the lag though.