Got back at the weekend from a week in Rome with the Mrs. Up to this point, my favourite city break had been Barcelona - but I have to say Rome pushes it very, very close. It's absolutely beautiful with history everywhere you look. We had a tour of the Vatican and the Sistine Chapel which were completely breathtaking. Went in to the Colosseum (less the tour guide) and all of the other sites. I have to say in other European cities after dark they can become a little intimidating - but there was none of that. The Italians were extremely friendly and helpful - we saw no trouble anywhere. The food was a little hit or miss depending on where you end up, but we stumbled across a restuarant not far from the Trevi Fountain (which was about 100 yards from our hotel) called 'That's Amore', and it was absolutely fantastic - so much so that we went back there on our final night for a second time.
I would encourage anyone who hasn't visited Rome at least once in their lives to go because you won't regret it (and book a table in That's Amore). It wasn't any more expensive than other European cities I have visited (which include Barcelona, Berlin, Amsterdam, Paris etc) either.