That's frighteningly broad. Not only does Microsoft give itself the right to snoop through all of your information if it decides it wants to, it can also gather information that "Microsoft acquires about you through your use of the services (such as IP address or other third-party information)..."
Microsoft now claims that it will apply stricter rules about when it snoops on someone's Microsoft's mail and messaging account. But keep in mind that it's not changing its Terms of Service agreement, which means that whenever it wants, it can abandon those stricter rules and do whatever it wants.
So how safe are your private emails and messages from Microsoft? Not very. Whenever it wants, it can snoop on them. Ironically, Microsoft has been engaged in a massive marketing campaign against Google called Scroogled in which it points out all the ways in which Google invades your privacy, while Microsoft doesn't.
Ooops. There goes that campaign. Is there time for Google to launch one countering it, called "Microsofted?"
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