Wow ! some serious whingeing on this forum.....why does everyone keep going on about the Vulcan ? Sure it's an iconic aircraft but its far from the most entertaining airshow performer. I went to both RIAT and Waddington last year and there were some stunning displays and in my humble opinion two of the best were from a helicopter: The RAF Chinook and a transport aircraft : The Italian C27 Spartan.
I think RIAT continues to put on a very high quality display every year, despite the obvious challenges so if the F35 doesn't turn up......big deal it was never likely to put on a thrilling display anyway. I'm sure it will be a great day out with or without that ugly lump of tin !