Lol I also went last weekend, did Belfast for a couple of days which was grand and then visited Dublin for a few days, Dublin was over priced as hell. Guinness storehouse is amazing and very interesting, Temple bar in the Temple district could have been anywhere in Brighton on a Saturday night, although we did end up finding a pub playing live blues which was fun.
Have to admit Belfast was far nicer and more interesting than Dublin, Plus for a drive you can go to the Giants causeway and see a a bit more castle type stuff. Blefast has a rip off version of the London Eye too and also a new swanky shopping mall with a center spire that you can climb up and see all of Belfast. It's damn high!