Brian Seitz, writing on the official Windows Phone blog:
As many of you know, we are landing in San Francisco on Monday October 29th to showcase some new things from Windows Phone. For those that can’t join us in person, no need to worry! You can tune into a live webcast here, all from the comfort of your couch, cubicle or coffee table. We hope you can join us, see you on the 29th!
Here's the link to the newsroom for you to bookmark, ahead of Monday.