I've had a chance now to run some existing Keynote files through 1.1 and export them into PDF, QuickTime, and PowerPoint. I'm happy to report that most of these have been improved significantly.
QuickTime export looks great now (although, I thought it looked pretty darned good before). File sizes are still pretty big if you have animation in them.
PDF has improved significantly. Output looks great, but more importantly the file that used to output at 10MB now outputs at 2.2MB, which is a great improvement.
PowerPoint output is also significantly improved. There are still issues editing white text on a dark background (but, they exist if you do that using powerpoint natively as well), but notes are correctly kept and most of the graphics (including backgrounds) look quite good now. Transitions are nicely mapped (fly-ins now fly in, 3d transitions map to a fade transition) and things flow quite nicely.