Not sure if anyone is still having the 2012 calendar problem but I found a fix online last night that worked for me. I went into the PS3 browser and cleared the cache. I then uninstalled the MLB.TV app and re-installed the same version. Rebooted the system and voila! 2013 calendar! I probably could have skipped the uninstall/reinstall step but I figured it couldn't hurt to try that as well.
Now I just need to test if the games will actually play.
Now I just need to test if the games will actually play.