A features post on the Official F1 site briefly reviews the idea of track evolution: Track evolution - the change from green to mean.
The press-released FIA timing data doesn't provide sector times for P1-3,and only provides best lap sector times from qualifying and the race, so we can't use that data to get much of a feel for track evolution. However, I have been pondering some simple stint models, and I guess 'trackEvolution' is one of the factors that might play a role in that?
In other news, for those of you lucky enough to be able to gain access to academic literature, this might be of interest: Automatic Track Generation for High-End Racing Games Using Evolutionary Computation, Loiacono, D. Cardamone, L. Lanzi, P.L., IEEE Trans Computational Intelligence and AI in Games, Sept. 2011, 3(3), pp. 245-259