I don't even bother to watch our equivalents (Rugby and Australian Rules grand finals).
I could see myself getting interested in NFL if I lived in the US, it's an exciting game. But obviously I'd have to learn the rules: otherwise it's just big men in helmets randomly throwing a ball around and crashing into each other.
We do have one sport now that is very close in terms of duration to a Major League Baseball game (T20 cricket). I watch T20 domestic games fairly often, only been to one live game though. I've been to one Major League Baseball game, a very lopsided match between Baltimore and one of the Chicago teams.