IOC head Jacques Rogge was interviewed by MLB.com's Mark Newman and cited various criteria for Baseball to earn its way back in: "To be on the Olympic program is an issue where you need universality as much as possible. You need to have a sport with a following, you need to have the best players and you need to be in strict compliance with WADA
The London games are coming up later this summer, but for the first time in years, baseball won’t be a part of it. When baseball, along with it’s sister sport* softball, were kicked out (to later be replaced by golf and rugby), the most often cited reasons by the International Olympic Committee were (in no particular order):
A lack of popularity outside of the Americas and certain parts of Asia A steroid problem Not having the highest level (i.e. MLBers) play like the NHL and NBA do.