There is news about TomTom and TMC (Traffic Message Channel) . It seems that the longtime problems have been solved.
I have not really an idea about the situation outside Europe, but I know there are many TomTom users not very happy with the TMC reception of their devices.

Dutch website yourNAV is reporting about the problem and say that 60% (!) of the users is not satisfied with the function. The survey was made under the users of their forum.

The TMC ready range started with the GO 510, 710 and 910 that were introduced in March 2006. But it was not before September of the same year that the external TMC antennas were available
From the start it was clear that the receivers were not working like they should. And only now, after about a year, TomTom did find the solution.

The new TMC receiver (version 4V00.013) was tried out and instead of about twenty minutes there was signal in 10 seconds and it did not disappear.
The new antennas will be in stock withing a few weeks and will then be available in the shops too.

How to recognize the new antenna:

• the wire is quite a bit longer
• there is a third sucking cup
• after the first sucking cup the is a thickening of about 1 cm in the wire

via jouwNAV (the story itself is Dutch only)