In my original Longhorn build 4051 review, I focused on the events leading up to the Professional Developers Conference (PDC) 2003 and some of the more superficial changes Microsoft made between previous alpha builds and build 4051. I was originally going to follow that with an in-depth look at the various technologies exposed by Longhorn build 4051, but that portion of the review grew out of control. So here, a month later, I've reorganized. My full Longhorn build 4051 review will now be delivered in several parts, with the first two parts being made up of the original review.
In the subsequent parts, I am delving deeper into the technologies behind this build, and examining the crucial building blocks that will form the basis for the next Windows version. To understand or even discover some of these technologies requires experimentation with the Longhorn Software Development Kit (SDK), which exposes many of the features of this operating system programmatically, letting software developers create Longhorn compatible applications and services. So I've had to dust off some long-buried programming skills and get my hands dirty, so to speak, for the first time in several years. It's been an interesting exercise.
Source:
http://www.winsupersite.com/reviews/longhorn_4051.asp