Magnetic man are playing this year, not confirmed by Bloc but benga said himself at a recent gig in bristol.
I would say though that at all the Bloc's in the past year, they have evened out the genres nicely and there has never been too much of one particular.
I saw all of them in a car parked outside the Tesco near the Butlins on the first day. I took a picture of it but can't find it, it was all of them in like a cardboard lid thing.