I did some searching and could not find any information on this subject. I hope there are online ranks, because playing for one in Tekken 6 and SF4 is very addicting.
MK's online ranks have always been garbage. But seeing as how they are getting rid of the god-awful lobby, and applying the SSFIV endless system. I think things might change.
As far as an online fighter goes, im 100% sure it will have one. But I hope it works like SSFIV's grade-point system. Meaning you don't get to play people more advanced than you, unless you start winning more. Other than that, it all depends on how well the net-play will work for the game. If its as bad as MKvsDC, then a grade-point system wont matter.
Also, in past MK games, pulling goes unpunished...
I like the grade-point system, because even if you are online, at least you get to see yourself get better. Then you can take it to a tournament, and see how well you are doing. This of course is if you are playing people in your area... lol