In addition, think of this, right now Android ships with a webkit based browser, not a chrome based browser.
Imagine a time when android OS gets a Chrome based browser.
It seems to make sense that Google saw the direction of the mobile market with their Android initiative but were a bit surprised at the growth of the netbook market and the added interest in Android shipping with netbooks.
Some folks at Google probably saw the rise of the Kindle and the forthcoming CrunchTablet and of other connected web appliances like Verizon's home phone, kitchen appliances, cars, tv's etc and realized that a simple Web OS would be less bloat than Android for all these other needs.
So now the real market makers, manufacturers, will gain the same thing that the OHA folks have gained. A simple to use, open source, universal OS that has major developer muscle behind it.
Embedded OS war in set top boxes, autos, appliances and the like are really where the next battle lie and Google is lining nicely to meet these coming challenges with a simple OS. It was quick departure that might surprise the Android crowd, but really, is Android made for larger screens? Should it be?