I have to agree with Don Martelli that Wave and GMail should be merged. I was totally bummed out by the announcement of shutting down Wave and really hope that something happens with that technology. I was not as interested in it as I probably should have been, largely since I was waiting for the federation features to become available before I put any real thought into it. I certainly hope that Google will open up the source code completely, but only time will tell if that will happen or not.