I feel we need some more 'stoner rock' or 'dirty rock' sort of bands in the next lineup announcement (although I'm happy with absolutely anything and go to see new bands from all types of genres)
Bands like: Dorothy, Rival Sons, Clutch, Kadavar, The Datsuns, Radio Moscow, Psychedelic Porn Crumpets, All Them Witches, Dirty Honey (again!), Tyler Bryant and the Shakedown, Fu Manchu, Wolfmother, Thundermother, The Chats, Graveyard- there are lots of women orientated bands within this genre too (in regards to above comments) and also has a good balance with a metal lineup in general.
Looking at European festivals like Graspop, these sort of bands play every year but don't touch UK soil.