The PDC website has a preliminary listing of sessions that will be offered at this years event. Among them are a number of sessions on Microsoft's cloud-based services, and a few on Windows 7. Among the Windows 7 sessions will be one on the multi-touch APIs. Multi-touch was demonstrated earlier this week at the All Things Digital conference as a "snippet" of the features coming in Windows 7.
Head over here to see this list of preliminary session topics.