A UK retailer had listed (since removed) a curiously named "Mortal Kombat Arcade Compilation" and described it as "MK 1, MK2 and Ultimate MK" and "the first MK to have a High Definition aspect," reports Eurogamer.
The franchise rights to Mortal Kombat now lie with Warner Bros., which will be publishing Mortal Kombat 9, known as Mortal Kombat. It would not surprise me to learn that Warner Bros. would seek to re-release classic games in the franchise, similar to how Capcom has been re-releasing its legacy fighting games through PSN and XBLA.
Existing MK ports have been removed from PSN (Mortal Kombat 2) and XBLA (Ultimate Mortal Kombat 3) following the collapse of Midway.
The retailer listing, however, suggests a boxed release and was only listed for the PlayStation 3. A release date of November 12 was also listed for the UK. I remain skeptical, however, as any true release to this effect would obviously be labeled the "Mortal Kombat Arcade Kompilation."