For a long time I wasn't. As a kid I was a Red Sox fan, because it's sort of required growing up within twenty miles of Boston to follow at least one of the local teams, and I liked baseball a lot better than football, basketball, or hockey. My mother was a Red Sox fan, too, so I didn't even need to turn on the TV -- I could just wander in when she had the game on.
That childhood fondness peaked in 1967, unsurprisingly. When the '68 Sox didn't even come close to repeating, though, my interest began to fade a bit, and once I moved out of Massachusetts I only followed baseball intermittently. I did watch a few games now and then; when we lived in Kentucky I followed the Cincinnati Reds and got to Riverfront Stadium a couple of times.
I never did get to Three Rivers to see the Pirates when I lived in Pittsburgh, and I kind of regret that.
When we moved to Maryland, the local team was the Baltimore Orioles, and somehow I couldn't bring myself to get very excited about them. They were still the Enemy, really, the other team in the American League East (besides the Yankees) that had made life difficult for the Red Sox, and I just wasn't comfortable changing sides completely.
When Frederick got a minor league team, the Frederick Keys, that was cool; Frederick was closer than Baltimore and wasn't in the American League. A minor league game was a great place to take the kids on a summer evening, and we did that a lot.
And then the Red Sox changed owners and the new guys started to put together a great team and I started to seriously pay attention to them again. In 2003 they came so close, and in 2004 they won, won the World Series for the first time since 1918, and on top of that, after years of trying, Washington got its own team again! The Montreal Expos -- who I'd long felt sorry for -- became the Washington Nationals, and I had a real home team to cheer for again.
Since then, yeah, I'm a serious baseball fan. I follow the Nationals and have loved watching them build a winning team. And over in the American League, I'm still a Red Sox fan.
That's it; here's your list of handy exits: