One of the coolest examples of Silverlight 2 that has been announced at MIX is the Memorabilia viewer app created by Vertigo for Hard Rock Cafe:
The application allows you to drill down into a selection of the Hard Rock Cafe's massive collection of rock and roll memorabilia. You can use the deep zoom feature of Silverlight 2 to get extreme close ups of guitars, letters, and more from artists such as The Beatles, The Doors, Bo Diddley, and more.
One tip I wanted to make sure to share...the beta installer asks you to refresh the page once you've installed the beta 1 release of Silverlight 2. In some cases, however, you may need to close the browser window in order to complete the installation. If you try to run the application, and get the error icon in the status bar, try closing the browser and restarting it, and you should be able to view the app.
I've run the app in both IE 7 and Firefox, and it's a great example of what is to come with Silverlight 2, and if you're a rock and roll fan, it's definitely something you should take a look at.