I'll be out at Google I/O on May 19 and 20, talking up the work we've been doing with EMF on GWT and just generally learning more about all the great Google technologies we depend on.
Regarding EMF support for Google Widget Toolkit, we hope to have a working implementation of full modeling support for GWT applications before too long. Ed has been hard at work on this, and we'll soon have optimized object serialization between client and server, and a generic GWT editor for EMF-based models. We think this work will be really useful for GWT development once it's done.
With respect to other Google technologies, Cloudsmith is particularly interested in App Engine and BigTable; we're using them now but still coming up the learning curve. Next after that is Wave, which we'd like to use but doesn't seem quite ready for prime time. We're hoping/expecting to see a renewed Wave commitment and inspirational roadmap from Google at I/O next week.
Planning on being there? Let me know if you'd like to meet up!