Two episodes have been registered with US Copyright Records. Since "Life: A Loser's Manual" has been announced as the 12th season finale, I think it's a pretty good indication we'll have a 13th season.
The episodes: "Abraham, Martin, John and Bobby Hill" has been listed for awhile, but I'm guessing it has some religious references and they're putting it on hold, since it was originally listed as a season 12 episode. The other episode, "Lost in Myspace" is production code CABE14, so it's either the 13th season premiere, or it might have been incorrectly announced that "Life" was the season finale. Of course, KOTH production codes rarely indicate what order or season the episodes are in.