jbm's blog on ver 0.9.3 mentions "Improved motion tracking: Kdenlive can also now analyse an object's motion, and the result of this can be used as keyframes for a transition or an effect. For example, you can now have a title clip that follows an object"
Hey, How do you use this feature?
Links:
[1] http://kdenlive.org/forum/users-forums/video-effects-and-transitions