MLB does a pretty decent job at promoting regular season games, but trouble with promoting the World Series.
That can be solved if either the Red Sox or Yankees moved to the NL.
But seriously, look at the contrast with the Super Bowl, one of the best promoted sporting events in America. The NFL gets the media from not only the cities whose teams are in the game involved, but local media from all over the world involved in the run-up to the game. They have specific media days where players and coaches must be available to ALL media, not just their hometown reporters and ESPN. It does not appear that MLB engages in local media for the cities that are not represented in the World Series other than sending out press releases with the game times and starting rotations. With the Super Bowl, we see personal stories in local media about some of the players, including players who are not studs. We don't see much of that about the players on the World Series teams in local media.
Selig and Co. need to seriously examine their media relations department and work on selling the World Series as America's Event nationwide.