I have been reading quite a bit on Team System lately, from a preview book I got from a raffle at our local .NET user group meeting. I find it really amazing and I would be the happiest soul if it is used the way it is being dreamt of being used! It's been close to 10 years for me in this industry and I have seen the ups and downs. For the most part, I have been really disturbed by the poor coordination with in the team itself. Not only among team members, but there is a communication embargo from the manager to the developer. Only the management has the vision. And it depends upon their level of involvement which would really mark the success of a team and the goal itself. Delegation is good. But delegating and then forgetting is REALLY BAD!
Tools like Team System would be a failure if there isn't the right thinking in the team.