Adobe Flash Player “Square” is a preview release of our 64bit Flash player for Windows, Mac OS, and Linux operating systems. It also provides enhanced support for Microsoft Internet Explorer 9 Beta. We are publishing this preview so that users can test existing content and new platforms for compatibility and stability. And yes, that means that, as a preview version of Flash Player, it is not as stable as a final version, so use caution when installing Flash Player “Square” on production machines. Flash Player “Square” is now on Adobe Labs. More details on the Flash Player team blog.