Paul Thurrott has been covering Vista builds for some time in his reviews and articles, often testing Diskeeper 10 as part of the review. As he noted in his latest review (http://www.winsupersite.com/reviews/winvista_rc1_03.asp) there are ways to get Diskeeper installed on Vista RC1. I completely agree with his comment that it's not a good idea to run Diskeeper on RC1; that is, until we officially offer a product. Those who have tested the current Diskeeper betas for Vista have noted that some features are disabled or reduced in functionality. That is because we haven't fully tested them. I don't anticipate anything breaking, but some of our advanced features (e.g. FragShield) do some relatively fancy things (on Win2k and XP) that may not carry over well to Vista without proper adjustment on our part. For the patient enthusiast, we'll have a new RC1-compatible beta soon, and a "full" product when Vista is officially released. ---- Having written a paper on the subject earlier this year, I was interviewed by Processor magazine on server virtualization a couple of months ago. While a few points I discussed were slightly muddied in translation (e.g. "CPU searching for files" is technically incorrect wording - but at least conveys the message) the interview covered some points system administrators/computer power users need to look out for when building these systems. Virtualization is a popular buzz word these days, but it is important to use this technology in the right places and under the right circumstances. That concept, everyone interviewed for the article agreed upon. There was, however, some debate on the importance of defragmentation. Alessandro Perilli, well-known virtualization expert and host of virtualization.info (the leading independent site for everything you ever wanted to know about virtualization) added his comments on the subject as well. http://www.virtualization.info/2006/08/is-defragmentation-real-benefit-for.html You can also check out Michael Otey's (Windows IT Pro) earlier "top 10" in February 2006, which counted defragmentation among the key priorities for VM performance. http://www.windowsitpro.com/Article/ArticleID/48726/48726.html?Ad=1 The simple fact behind these expert's viewpoint is that the disk is the weak link in a modern, general purpose, computer, slowing everything else down (where disk access is required). Alleviate the bottleneck and the whole system works faster.