I used Keynote for the 1st time in a University class I teach 3 days ago. Let me first say this thing rocks!
Once hyperlinks and the ability to play music throughout a presentation are implemented, it will be amazing.
I exported to PowerPoint for 3 reasons:
1. I wanted to check if it would work.
2. I wanted to see how close to the original the PP version would be.
3. I needed to generate a handout from the presentation. On this, let me say that the PDF export in Keynote is great, but it creates HUGE files, which is bad for my web space and bad for people on slow connections.
The program did a good job of creating a working PP pres. which included a lot of the same effects, although not as smooth since PowerPoint does not take advantage of Quartz the way Keynote does.
I guess I should also wish for the ability to export from Keynote straight to text, like PP does.