Adobe Labs (http://labs.adobe.com/technologies/flashplayer10/) has released a preview version of Flash Player “Square” that enables native 64-bit support on Linux, Mac OS, and Windows operating systems.
Adobe says they’ve made this preview available so that users can test existing content and new platforms for compatibility and stability. Because this is a preview version of Flash Player, don’t expect it to be as stable as a final release version of Flash Player. Use caution when installing Flash Player “Square” on production machines.