On RPGnet there's been three excellent threads for Doctor Who fans.
Doctor Who Campaign: The Stardust Memory Chronicles - Excellent multi-session actual play report. Reading this makes me want to run a Who campaign.
[Doctor Who] What do you have to know to run it? - Not as practical a thread as it sounds, but lotsa nerd-ramblings about the show.
Doctor Who - His Lives and Times - Excellent summaries of pretty much the whole of the old series by Who fan and RPG regular Topher.