Earlier today I stumbled upon this software : LongoMatch.
It's Open Source and multiplatform (Windows / Linux).
LongoMatch is a sports video analysis tool for coaches and sports scientists, to assist them on making games video analysis.
It simplifies video analysis by providing a set of intuitive tools to tag, review and edit the most importants plays of the game.
So at a first glance it looks like it is specialised in one of the things Kinovea doesn't do yet: analysis tool for longer videos. (read: team sports)
Segmenting, identifying plays, creating new videos from selected sequences, etc.
I could't really try it yet but I'm pretty interested in this. It sounds like a very promising effort.
If you have tested it, I'm curious to know what you think.