So – looks like end of the road for google Wave. Easy to knock google for this (and other initiatives that have not worked). Seemed like Google were in too much of a hurry to get the incomplete product out in the marketplace. Then seemed like they made some mistakes around security.
At the time I had a concern that in trying to develop a collaboration/ enhanced instant messaging et al tool they were going to build a monster. And I think that was a major part of the problem – user adoption failed because it was not clear which problem google wave was solving.
Anyway the technology is there for others to access and seek to incorporate into other products.