CoolTechZone.com has posted a Windows Vista Build 5231 Review

This is possibly the only application with more anticipation surrounding it than Internet Explorer 7, if not Vista itself. We wonder if Microsoft would bundle Windows Media Player 11 with Vista exclusively or would it be available for download separately for Windows XP as well. It most certainly will end up looking a lot better (graphically) than most music players out there, iTunes included. Although it appears to look pretty straightforward, the interface has changed drastically, which makes it far more attractive than Windows Media Player 10 as well as competing applications.

Windows Vista Build 5231 Review