I think if you take a chance on Tatum Bell as a RB2, or bench RB (depending on league size).. you might as well grab KJ 2 rounds later as insurance.
Personally, I don't see myself taking either in a redraft.
"Up until now, there had been questions surrounding when Jones might be able to return. Now the Lions are hoping Jones will be able to return six to eight weeks into the 2007 season, which means that Detroit must revise its offseason priorities. "
http://www.nfl.com/nflnetwork/story/9988518
I made the above statement going on the stories I've heard that KJ will not be ready to possibly mid-season, i.e. he might only play 4-8 games. Even when healthy, Jones is the kind of guy who RELIES on his speed and prefers to try and break a run outside and not wait for his blocks to set, rather than take the inside lane and pick up 4-6 yards. His yards per carry were good his rookie year, but once the scouting report got out on him, the past two seasons he's had 3.6 and 3.8 ypc, and he has yet to start a full season without breaking down. Obviously in 2006, KJ had good numbers overall with all the passes he got in the Martz system,
but I can't see the Detroit feature back being a key component of a majority of fantasy championship teams in '07.
I would think in a redraft, non dynasty league, Tatum Bell would be drafted by round 4-5 assuming he will be the feature back, while KJ would be a guy you can take a flyer on and stash on your bench if you have a deep league.
Still I would rather use a draft pick on a rookie RB and hope he turns into a MJD or Addai,
rather than have an injured player on my team for two-thirds of the fantasy regular season.
The 10-team $ league I'm in allows 2 keepers and then its redraft; my keepers are Edge & Chester. Nobody is keeping KJ or Tatum, so I could see them going in the 3rd or 4th round (really rd5/6) of our draft. I did a mock draft simulation for my league last week and I have Jones projected as the 50th player off the board after a run on mid-level fantasy RBs (Julius Jones, Jacobs, Ahman Green, Benson), as the RB3 for a team w/ Westbrook & McGahee.