Microsoft is the largest, most profitable software company in the world.
And its profits are still being generated by the same engines that have driven Microsoft for years: Office, Windows, and its server division. (Meanwhile, its entertainment and devices division is only recently profitable again, and its online division is a money pit.)
This is why Google is increasingly focusing on disrupting Microsoft's core businesses, including its Google Docs rival to Office; its Chrome OS rival to Windows; and now Google Buzz, an add-on to Gmail that some have compared most closely to Sharepoint, one of Microsoft's enterprise tools.
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