That was Eddy Cue. He seemed to be uncomfortable in this situation because he was looking down at the teleprompter the whole time (hence the correction you not

That was Eddy Cue. He seemed to be uncomfortable in this situation because he was looking down at the teleprompter the whole time (hence the correction you noticed, and the flat jokes). Even though he's prominent in the company, I don't think he's been on stage much. The other jokester was Roger Rosner (on the left in the "revise the record cover" demo, at 50 minutes into the keynote), who co-founded a startup called Lighthouse Design (http://www.langreiter.com/space/Lighthouse+Design http://www.langreiter.com/space/Lighthouse+Design), which, in dinosaur times, developed the presentation program Concurrence for NextStep. That's Roger at the top of the stairs in the photo above. Concurrence eventually was rewritten at Jobs's request, and became Keynote. Roger also hasn't been on stage much, but he's a good guy, and a real developer, so cut him some slack. (Incidentally, the guy at the very bottom of the stairs is Jonathan Schwartz, who eventually became CEO of Sun, but was not really a developer.)