I just released Thunar-0.2.0alpha and libexo-0.3.1.2alpha. As the name suggests, it's an alpha release and it is thereby considered to be more or less stable in what it does, but it's by no means a final version.
You'll need atleast libxfce4util 4.2, Gtk+ 2.6, shared-mime-info 0.15 and desktop-file-utils 0.10 to build and run Thunar.
The official announcement is available from: http://thunar.xfce.org/news.xhtml
The source tarballs are available from: http://thunar.xfce.org/download.xhtml
Please report bugs to the Xfce Bug Tracker (product Thunar) at: http://bugzilla.xfce.org/