EDDNR:
Sorry, this reply is too late for the BBMF day (today 5th May), The main airshows this year are 20 May; 7&8 July; 8&9 September and 14 Oct.
You can fly into any or all of them. You need to read the 2007 AIC (28/2007 Yellow 239), which you can get from the AIS site or by email from Duxford. You need a slot which you can get by phoning the tower with the AIC in front of you 01223 833376. There are still slots available for all the airshows.
The BBMF day today was very nostalgic - Spitfires and Hurricanes; the Lancaster which brings a lump to your throat and, by way of a complete contrast, the Typhoon, which flew a duo with a Spit followed by its solo spot.
If you can't make the airshows, come for one of the Bonus Days. You'll be welcome.
I'll double check the web site info next time I'm there.
All the best
Alan.