Google's plans have always been ambitious, but they've recently stepped up their game in a big way. No longer content to have your email, documents, calendar, credit card info, and all the rest of your personal info and computing attention, now they're setting their sites on the final frontier: the entire operating system. In what can only be explained as supreme power-play, and a credible threat to Microsoft, Google apparently wants to control it all. The new operating system will be built around their Chrome web browser; apps will be hosted by Google, and will be centrally served from Google's servers, working in the browser. Fixes, updates, and such will all be handled directly at the source (Google's own servers, in the same way that updates to Gmail, documents, and all the rest of Google's properties happen). The advantages to this are enormous, but it remains to be seen if this setup will be robust enough for real work.
At it's heart, this will likely be a resurrection of the networked thin-client which was so heavily hyped in the mid 1990s.
It didn't work then.
But this is Google. And it's going to be one heck of a ride.