The TMC system works pretty well and allows for dynamic routing around problems. The main issue with it is that it's only as good as the data provided by Trafficmaster. They only cover motorways and major A-roads so it's useless on anything else plus there'll always be a bit of lag before incidents are reported and logged on the system.
The Internet-based systems like Google traffic or the Tomtom live systems use crowd-sourced data where everyone using the system contributes by uploading their location and speed and so forth. The servers can thus generate a much more detailed and up-to-date picture of traffic problems. AIUI, the new Audi Connect systems, as recently made available on the A3, will allow you to make use of Google's crowd-sourced traffic data for navigation instead of TMC.