It looks like Microsoft is really trying to keep up with digital media and have opened their very own online store. As you might have guessed, it's aptly named, Microsoft Store, and they are selling just about everything Microsoft.
This online locale is where the company is selling things like Office, Windows and their branded peripherals like mice. Plus, you can buy Xbox 360 hardware and software. This way all things Microsoft are for sale in one convenient place.
Zunes are available as well, as are various applications. In fact, some can be downloaded directly. You can now download Office 2007 and Expression. Though currently restricted to Windows apps, Office for Mac is one notable exception. You can go get shopping now at the US store as well as the Korean, German and UK versions. The French, Japanese, Spanish and Netherlands versions will be available soon.