I hadn't signed into Windows Messenger beta recently. They changed the look (again!). It's clearly taken on more of the live.com look that Microsoft has been pushing to many of its consumer web properties (like the new search.msn.com). Very clean/sharp. Such a change from last versions. It may be lacking though in personality. The minimalistic style lacks character and a strong brand image. Since there aren't very many instant messaging clients overall (compared to the number of web pages for example), maybe its OK.

It's got some bugs ... note how my Angry Beaver (a canceled cartoon) image wasn't carried to the actual signed in screen. It's chess figures below.