BBC for me, for the same reason as @markthornton90 primarily. I thought the BBC commentary team were very good at the weekend, and the pre and post race stuff was better than Sky, so for the live shows there should be no contest with the red button forum etc. Brundle and Kravitz are a loss, but the pros still outweigh the cons and the BBC offer a better product IMO.
Speaking of which – anyone know why there wasn’t a red button forum at the weekend? Jake Humphrey said at the Autosport show that they would film a Forum for every race, regardless of whether or not it was broadcast live.