That's a bit difficuilt to explain.

* The "original" version is maintained by Ralph,  you'll find this version
  at http://www.thp.uni-koeln.de/~rjkm/linux/bttv.html.

* I have my own tree, becauce I do some driver programming too, and
  sometimes I have to fix things which Ralph can't test.  This version
  comes with xawtv.  I try to stay in sync with Ralph, most of the time my
  version does'nt differ much from Ralphs.

* The kernel version is maintained by Alan Cox.  Both Ralph and Alan take
  care that they are compatible, but usually it takes some time until
  bugfixes/new features go from one into the other version.

There is no general rule to tell which one is better.  I personally use my
driver tree :-)
