Well, I finally got Office Beta 2 downloaded and all of my machines upgraded from Beta 1 Technical Refresh. So far, so good. Performance is still not ideal, but it's much improved from previous builds (especially in Outlook).
Microsoft released the first public beta (Beta 2) of Office 2007 today. I've been using this since the first alpha and I can tell you it's a marked improvement.
As I've said in the past, we should all be concerned about privacy even if you're not doing anything wrong.