There's been discussion on the MLB being realigned to have 15 teams in each league instead of the current 16 in the NL and 14 in the AL. Of course, the team that has been speculated to be moved to the AL is the Astros. It makes sense to foster a rivalry between the Astros and the Rangers...
This is not very likely to happen, but it's interesting to speculate on any major changes like this and to also think what you would to realign the MLB...
Here's the link: http://sports.espn.go.com/mlb/news/story?id=6651634
Here's the breakdown I just thought up in 5 minutes... it's probably way off base, but I was trying to think very simply.
3 division of 5 teams in each league.
15 games with each division rival (4 teams) = 60 games (it would have to rotate yearly who got the extra home stand)
6 games with each league rival outside of your division (10 teams) = 60 games
3 games with each opposite league team (15 teams) = 45 games
That would make the season 3 games onger, but at least the schedule would make sense... Feel free to destroy my simpleton approach.