A couple of weeks ago, some friends and I put together this little film : http://www.youtube.com/watch?v=QoSFuK3qAW4
The purpose of the film will probably defeat you (watching http://www.youtube.com/watch?v=4rF1mumdT9k&feature=related http://www.youtube.com/watch?v=_qOPk4TKBwY and http://www.youtube.com/watch?v=-c4UzbL7J-o might help, but the context is a bit too specific to explain ;), but it's just to show what is possible now with Kdenlive (made with non official Kdenlive 0.7.7 from the sunab2 repository on Ubuntu 9.10).
The editing was far from painless, but we listed the various issues we encountered (bugs and missing features), and I'll create a topic explaining what went wrong (and all the Bug Tracker tickets that go with it).
Anyway, I hope you enjoy it, and I thank all the Kdenlive, MLT and ffmpeg developers that made such a great program possible !
Edit : here's the topic containing the vairous problems we encountered : http://www.kdenlive.org/forum/feedback-after-using-kdenlive-real-project