The CvsGui project is providing several high-end interface clients (WinCvs, MacCvs, gCvs) written in C++ using popular frameworks (MFC, PowerPlant, GTK+) with a scripting support via Python or TCL.
wxCvs is a cross-platform GUI frontend to the GNU Concurrent Versioning System (CVS). It is written in python and uses bindings to the wxWindows C++ cross-platform GUI toolkit (http://wxwindows.org). The python bindings to wxWindows is known as wxPyton