he new build, version 5744, is made available to a far smaller group and technical beta testers, TAP testers, and MSDN/TechNet subscribers. Within days, Microsoft said it will extend the download availability to participants of the Windows Vista Customer Preview Program.
According to Microsoft, about 100,000 users will get a version that fixes "many bugs" that were found in RC1. Platforms and services co-president Jim Allchin wrote in a message to beta testers that Microsoft has implemented "thousands of quality improvements" that are likely to result in performance improvements as well as application compatibility.
Microsoft intends to continue to work on the software throughout the RC2 period, but mentioned that it is close to actually release the code to manufacturing (RTM): "We are just around the corner from RTM and shipping this great product to the world. This will be the last build made available prior to RTM, so please keep the feedback coming so we can hit the finish line," Allchin wrote in his message.
article from tomshardware.com