Just wasted my time paying attention to the #WP7Dev hashtag on Twitter just now, I (as well as other developers I think) thought it was to coincide with the announcement of the available frameworks on Windows Phone 7 Series done here. Another interesting thing to find out was that MS is still gonna push WM6.5 hmmmm, most likely WM6.5 is gonna become the preferred Enterprise App developement platform for writing company specific applications and the like, and WP7 for end users. That'll make for an interesting split... we'll see what happens.
So I was right about my predictions on XNA support in Windows Phone 7, I wouldn't call my prediction that Silverlight 4 support is right until they announce it at MIX, this is because from my point of view. The SL4 beta that we have access to is not fully suitable/capable of being an actual client framework yet. Hopefully something will change at MIX '10
Which was my main peeve about the Q&A session just now. They called it a Q&A session, but when most questions could not be answered, or had to be answered with a WFM (Wait for MIX) remark. WHY DID THEY EVEN BOTHER TO CALL IT A Q&A!!!
Just make the announcement on Twitter about the frameworks and leave it at that then, then people won't be pissed when they can't actually get any answers out of you since you never said you'd answer questions!