I agree, this is just an excuse for a quick cash in, but I gotta admit, I kind of like the idea... and the gameplay doesn't look to bad either, this could actually turn out good.
BATMAN !@#$% YEAH.
Edit: Now that I think about it, the whole "fatalities" thing, perhaps they won't include them, but that wouldn't be very Mortal Kombat like... they may just include a "finisher" type thing, but nothing that kills.
Not sure, just have to wait and find out.