The site features a new layout, with more focus on directing users towards security and feature updates like service pack 2 for Windows XP. The navigation also appears clearer, allowing easier access to the many parts of Microsoft's site.
One problem that still remains, however, is the site's lack of standards compliance. It doesn't validate to the very basic (and somewhat aged) 4.01 HTML standard. Also, the site appears quite different in non-IE browsers - Firefox users don't see all elements of the site, and they also enjoy 'poor' images due to DHTML image rendering filters. See this post for more information.