Well, in the "You just never know" category, Crosman was purchased by Compass Holdings a couple years ago. I've watched some subtle changes at Crosman and their product lines. Seems just as much on air guns, and even more on Archery and Optics. Seems someone is funding stuff over at Crosman. So, maybe someone got the semi-auto bug and developed the gun. Updated breech on a Marauder frame shouldn't be that hard to develop. 60 shots per fill would also mean regulated.
My guess is the advertising is real, Midway may have just put it up early. The advertisement may disappear if it's a mistake, but it could portend the next generation of Marauder, keeping it relevant in a highly competitive world.
My biggest complaint with my Marauder is the bolt pull effort. A Semi-auto would completely eliminate that complaint!
I hope it's real, I hope it's real, I hope it's real, I hope it's real, I hope it's real, I hope it's real, I hope it's real, I hope it's real . . . . . . . . . . .