I gave a talk at ICPSR yesterday on "the cloud." I used Prezi for creating and playing the "slides," and you can find a link to a copy of it here. And I will also embed it here:
I used the iPad 2 to play the presentation, and I think it worked pretty well. The Prezi iPad app does not support video or audio at this time, and that meant I could not include a few clips I had planned to use. If the Prezi guys can fix this up, I think Prezi and the iPad will be my new main platform for giving talks.