Steven Sinofsky has confirmed that the beta we are all using and loving is the only one we’ll get. The next step will be the Release Candidate (RC) which will have a complete feature set and be very close to the final version.
His statement included:
“We will continue to listen to feedback and telemetry with the focus on addressing only the most critical issues that arise. We will be very clear in communicating any changes that have a visible impact on the product. This release allows the whole ecosystem to reach a known state together and make sure that we are all ready together for the Release to Manufacturing. Once we get to RC, the whole ecosystem is in “dress rehearsal” mode for the next steps.”
MS are still stating Jan 2010 as the release date as this fits 3 years after Vista, but I along with many others, think that Q3 this year is more likely.