Here's the rundown.
You have the same service record rank. You know, general, or whatever, from getting a 50 and 600 exp, etc. In addtion, a new playlist rank has been adding for each playlist which is based only on expirience. Each time you win, you get exp for the list and move up through. Skill does nothing for this playlist rank. The playlist rank only has to do with one specific playlist, not the game in general.