Too soon for a full frame to come out, imo, but they could always announce it on the same day they come out with another product.
Last fall, there was a rumor on here before a tradeshow (PMA?) that the 24 MP APS-C was being delayed until early 2013 and that a refined K-5 would be released at the trade show instead, and the refined K-5 part of that rumor turned out to be true with the K-5 ii. Going off that rumor and Ricoh's only recently public suggestion of work on fullframe I've been assuming a higher level APS-C camera in the spring and a full frame camera possibly by this fall at the soonest.
Then again Pentax has a lot of holes to fill so it could be just about anything. An entry level camera is possible. Maybe Ricoh's rumored APS-C point and shoot. Etc. etc.
But one never knows which rumor to believe on here so we'll have to see