I think Cook and Strauss will be the stars in the batting line up, Pieterson and Flintoff will make vital and valuable contributions but due to their flamboyant approach they will have a few failures, where as both Cook and Strauss have the temprement to dig in and build innings.
As for the bowlers, I think Hoggard will be Mr Consistent and if he can get some early swing and seam movement he could cause the Aussie batsmen problems. Panesar will be targetted by the Aussies IMO, but he has ability and I can see him picking up quite a few wickets.
Collingwood's fielding could be key as well, on fast bouncy wickets, he will IMO get a lot of half chances as the batsmen are likely to play a lot flashing, agressive drives which will see the ball flying off into the areas he likes to field. His ability to pull off stunning catches could be key in what is sure to be a tight series.