Microsoft Corporation (NASDAQ:MSFT) made deals with companies such as Porsche and Pepsi that will enable the companies to integrate their brand into the operating system. The branding may include borders and sounds.
The advertisements could also extend to the Internet Explorer 8 browser that comes with Windows 7. Internet Explorer 8 would have add-ons that link to the homepage of the brand. There is also a version of Office called Office 2010 Starter Edition which is limited and is funded by advertisements.
Interestingly Apple Inc. filed a patent recently that revolves around advertising on an operating system. The operating system would limit functions until the advertisement is done.