Improve multi language support
There are new ideas introduced in WPF with x:Uid in XAML and locbaml command line tool but the translation process is a mess, see http://wpflocalization.codeplex.com/
There should also be a standalone resource editor available for translators.
Thomas Levesque commented
Yes, localization is definitely one of the things to improve... Why not take advantage of the existing ressource mechanism (.resx files) ? One can create its own localization framework using markup extensions or attached properties, but it would be better if there were standard built-in tools to do it...