Microsoft isn't going to show Windows 7 to attendees of the Professional Developers Conference (PDC) in Los Angeles until Tuesday, October 28. But new info about what's part of the pre-beta build that will be provided to show-goers is beginning to trickle out. ZDNet's Mary-Jo Foley has used her sources to get some early details about what the build might include. According to her report, the Windows 7 pre-beta will introduce Device Stage, Action Center, a new framework for user-interface animations, and StreamOn. Device Stage will work as a "central location for customers to more easily interact with devices," while Action Center will help users troubleshoot problems, and StreamOn will have something to do with audio and video content—Foley says she doesn't know the specifics yet. Microsoft's PowerShell scripted command-line interface will make it into the pre-beta, too, as will the multi-touch functionality we wrote about in May. Foley claims the first public beta of Windows 7 will come out in the middle of December, with the final release to follow "by next year." Evidence of a 2009 launch schedule for Windows 7 has been piling up for a while now, so that's not surprising.