Yahoo releases Yahoo! Messenger for Vista
Yahoo just released their Yahoo! Messenger for Vista. I haven't yet installed it but I do know that's its based on WPF. Check out some of the blog postings about it, below.
https://eric.burke.name/dotnetmania/2007/12/06/0.05.32
https://blogs.zdnet.com/Stewart/?p=661
https://www.ymessengerblog.com/blog/2007/12/05/yahoo-messenger-for-vista-preview-release-available/