The first book to contain a significant section on DWR is out. It's called Professional Ajax, by Nicholas C. Zakas, Jeremy McPeak and Joe Fawcett.
JavaWorld has another article out on DWR - this time about creating Google Maps mashups. It's well worth a read ...
I've been on a quick trip to Stockholm to give a seminar on DWR for Crisp. I was quite surprised how many people there were there with only me for entertainment for 3 hours! From there I went to a castle in the middle of Denmark to the Javagruppen conference (pics) along with the Ajaxian guys which was also good fun.
The next trip is out to San Francisco for The Ajax Experience in May.