Looks nice but I was really hoping for <track> support - based on some recent testing, it appears that currently only mediaelement.js supports both the Flash fallback and support for subtitles / captions.
Note: I'm one of the developers of Flowplayer.
http://articles.boston.com/2012-06-22/business/32352980_1_di...
I'd honestly say it should have been a blocker but at the least it should be high priority for next release.
However, most web videos today are not associated with captions and made us ignore this from the initial release.
For the first release we picked the ones we thought were absolutely necessary to make a great product. For the next one we fill in the gaps. For some people captions are highly critical and we cannot please them with Flowplayer 5. For them we recommend our flash offering
until captions are implemented to the HTML5 version.