MLB 2K12 is most likely going to be the last MLB game from 2K and Take Two Interactive, and according to Kotaku, Take Two has pretty much confirmed that they will not renew their license with MLB.
"Our legacy Major League Baseball agreement will sunset in fiscal 2013. MLB 2K12 is our last offering under that agreement. At this time, we have no further comment," said a Take Two spokesman to Kotaku.
2K has not listed MLB 2K13 as one of their upcoming titles, which they did before when they dropped their NHL and college basketball series. Strauss Zelnick, chairman and CEO of Take Two, has repeatedly said that the MLB license has been a financial loss for them. The writing is definitely on the wall, now it's just a matter of 2K or Take Two officially confirming it outside of a spokesperson's statement.
If this does come to fruition, then baseball gaming fans will need either a PS3 or a Vita to get their fix. MLB The Show seems to be the better of the two games anyway.