[patrickt]

The pictures showed a crease that ran along the middle of the leather seat where the water had puckered the leather. In this type of situation there are two things we could do, one is sand the crease out and with some fillers and dye make the seat new again, this is where a leather professional comes in to play, or replacement of the section that is creased, that's where an upholstery shop comes in. In these type of situations there aren't any leather conditioners or cleaners in the world that will remove a creased or puckered leather, what happens is the actual structure of the fibers in the leather have been altered and what you see is what you have.

Source: How to Remove Stains in Leather Seats http://ezinearticles.com/?How-to-Rem...ats&id=1283445