I live in Scotland, and at the moment I'm going to
T in the Park, and I'm going to get a ticket for
Connect Festival.
If you can't be bothered clicking the links, the pick of the bands at T in the Park are (in my opinion): Rage Against the Machine, Aphex Twin, Justice, Pendulum, MGMT, R.E.M., Ben Folds and The Chemical Brothers. I am definitely looking forward to this fest, as I would happily pay the ticket price for RATM alone. So, it's going to be awesome. That's at the start of July, so it will also be sunny - a bonus, though, as it's Scotland and you can never guarantee sun.
The Connect Festival is a different festival, it's held in a castle, and the highlights of that weekend, for me, are: Bloc Party, Sigur Ros, Asobi Seksu, Crystal Castles, The Roots, and The Coral. This festival doesn't have as good a lineup, as it only started 2 years ago and is still struggling to compete with T. But I'll still enjoy those bands and there's more to be announced so hopefully it will be better than the Kaiser Chiefs or Franz Ferdinand, ugh.
Anyway, give us details of festivals you are going to and the highlights of the lineup for you. Also, please include a link so we can check out the lineup for ourselves.