The cutting edge of DWR development is being presented at SpringOne this week, and frustratingly I can't get there to hear it; Bram has been working on getting DWR v2 working with Spring 2 namespaces.
The idea is that you'll be able to configure DWR easily from within a Spring beans.xml file which should make configuration from Spring much easier. I'm sure Bram will blog his slides when he is done, and you can download a preview of DWR 2.0 milestone 3 here.
Update: Bram's slides are now available. The really cool slide is this one: