Not much, besides really good brand recognition. But it does show that Microsoft is starting to take another strategic shift toward emphasizing software as a service. Actually, it’s been trying to do that since .NET and the ill-fated “HailStorm” in 2001, only now there’s actually a business model to go along with it — advertising. The best commentary I’ve seen:

Now, Windows Live doesn’t look too impressive at the moment — mostly a bunch of rebranded MSN services that don’t work in Firefox, and barely work in IE. But guess what? Windows 1.0 was pretty bad too! While it’s too soon to say Microsoft will be successful, underestimate Microsoft at your own peril.