There's an interesting New York Times article about Beta Testing for the sake of `bleeding edge' status here. It mentions:
Software testing used to be done by serious computer users. Now, testers are motivated less by service than by the status of being among the first to try the newest software.
This is a trend that I've noticed increase as well. Various pieces of software seem to be more and more anticipated all the time. Microsoft Employees were recently eligible to participate in the Halo 2 Beta, which has spurred some bragging from those involved. The cutting edge of the technology curve is a tough place to get to, and an even tougher placer to stay. Beta Testing is a great way to enable being the first kid on your block with the latest toy, and the joy of searching for bugs can be even more fun that using the software like a `normal' user.
Want to try out Beta testing for Microsoft products? Visit Betaplace.