This presentation compares Flex versus HTML 5 in terms of features that compose a typical RIA (rich internet application).
This talk given at Ignite Sydney 2009, where every talk was 20 slides, 5 minutes, 15 seconds each slide. These slides have been annotated with the narration from the talk. Check Youtube soon for the actual video.
Relevant links are in this blog post:
Clipping is a handy way to collect important slides you want to go back to later.