I attended the Sunday night game in Atlanta on Memorial Day Weekend. Braves fans were stereotypes of southern hospitality: everyone I sat next to engaged me in conversation, despite the fact that I was wearing a Nats hat and an Expos shirt. They said some nasty things about their own team, who were on a 7-game losing streak at the time, but they weren't rude to me or to the other Nats fans there.
I stayed in downtown Atlanta, and I took a shuttle from near the state capital building to the stadium. It was fine.