[url=http://www.macromedia.com/software/flashplayer/public_beta/]Download the beta here[/url]
Macromedia has released a public beta for testing existing sites with the most recent build of the player. So download it from the link above and check you stuff! If it no-worky, then let the good folks at Macromedia know pronto so they can check it and fix er up.
There are links and more info on the download page for unistallers, and reporting bugs.