For this preview, I had originally written a long-winded backgrounder about the history of Longhorn, and the ways in which this project has changed over time. I'll save the lengthy exposition for a future review, however, and get right to the point: Longhorn is now considered a major Windows release by Microsoft, and early alpha builds are now testing at the company's Redmond campus. Last month, some of those builds leaked to the Internet, causing a stir in the Windows enthusiast community. I take a look at one of those builds here.