It seems that many people who bought BMWs recently don't have operational TMC.
I'm not sure if it's just the DVD, or a full software upgrade, but mine (ina 3 series) is 2004-2 and the TMC works fine. Signals are broadcast on RDS channels with the traffic information, and are operational now.
It works fantastically - getting you around jams, re-routing etc. So, if you have a car with the TMC feature, but it's not operational, ask your dealer to get it going!
Simon