IE8 is the new IE6. No native audio/video support.
You can use popcorn-ie8.js but how does it play the media?
Answer : Flash! (Saviour of the Universe) Not really of course.
Note: Main reason Flash is a problem, is not its closedness, or the black-box mentality or the performance - it's the security issues.
The Popcorn player does not include a Flash fallback and Vimeo and YouTube players are rigid UI-wise.
We wrote a jPlayer wrapper for Popcorn. Which means we can use jPlayer's Flash fallback and totally customise our player.
popcorn-ie8.js + popcorn.jplayer.js + jquery.js + jquery.jplayer.js ( + jplayer.swf) ???
If you need maximum browser compatibility and/or only have media in one format and want visual contol of your player. Possibly.
Note There may be wrappers for other media libraries. I couldn't find them.