Nice recognition of what Windows Live does to hook-up to Microsoft and non-Microsoft services: 

[...] if you are a newcomer to Windows Live and check out the applications, either as an all-in-one download or piece by piece, you will discover one very un-Microsoft feature: They are not designed to work only with Microsoft products.

Take Windows Live Mail, for instance. The e-mail program can download Web mail from Google's Gmail and from AOL, as well as Microsoft's own Hotmail.

Or the new Photo Gallery: You can also upload your Windows Live-enhanced photos to Flickr, the picture-sharing Web site run by Yahoo.

Full article: Microsoft decides not to go it alone - International Herald Tribune