leather seat care

For abrasion protection, I'd recommend seat covers. Real sheepskin seat covers.

Cleaning won't stop the wear and tear, and like any painted surface in a high traffic area, the paint will chip away. This is what is happening to your seat.

[Ronzi]

All of the swell leather care products will keep your seats clean, soft and supple, etc., but once you start wearing the finish off, i.e.,the abrasion problem, about all you can do is dye the leather back to it's original (hopefully) color.
Shoe dye is one option, although I'm sure there are others. Be very careful if you go the dye route, as you can easily end up with a bigger mess than you started with. If you have black seats, a little black shoe polish used sparingly in the appropriate place can work wonders, although you might want to henceforth wear black pants most of the time.
The question at some point is, should the seats on a car with 60,000 miles on it look the same as the the seats on one that has 10,000 miles? In the antiques trade a little wear I believe is called "patina", a quality much appreciated by European car collectors. On this side of the pond we seem to prefer the as-new look, regardless of age.

[KevinH1990]

If the bolster is already in pretty bad shape, you could have it filled and re-colored. I had that done on my Infiniti and I'm pleased with the results. You can see the difference in the pictures I've attached.

The best way to find a specialist in your area is to contact a luxury car dealership and ask the manager for the name of the person who reconditions the leather in their used cars.

Ronzi, patinas do form on leather, but only aniline dyed, not pigment dyed. Pigment dyed leathers (which most auto leathers are) simply get worn and dingy and look ratty. The pigment is a lacquer sealer coat that is essentially like painting the leather. It does not allow the penetration of stains from spills, but it also does not allow oils or conditioners to soak in. At least until the finish begins to crack.

A patina on leather is something that must be seen; it is hard to explain. It is a warmth and mellowing of the leather, as it darkens with use and time. Not unlike an old piece of unsealed wood that has been rubbed and polished by human hands over the decades.

[Ronzi]

I suppose we could argue ad infinitum about the definition of "patina", but wear marks on leather would seem to me to qualify as patina, regardless of the type of finish put on the leather. One man's dingy, worn, and ratty, is another man's patina.
In any event, my point was that absolutely as-new seats in an otherwise appropriately worn automobile mileagewise brings to mind the picture of the pig in a tutu.
You bring up an interesting point with your observation that pigment dyed leathers essentially have an impermeable finish. If this is the case, then seat treatments that promise to restore natural oils, soften the leather, etc. are just so much hogwash, not so? The stuff's not going to penetrate the finish, anyway.
So, the redoubtable MNBox is right again! Save your money, boys, and use the dish detergent from the kitchen instead of buying leather conditioners at $20 a bottle.

You bring up an interesting point with your observation that pigment dyed leathers essentially have an impermeable finish. If this is the case, then seat treatments that promise to restore natural oils, soften the leather, etc. are just so much hogwash, not so? The stuff's not going to penetrate the finish, anyway.

I mentioned this before, back in December...
http://www.986forum.com/forums/showthread.php?p=32395#post32395

The products WILL restore natural oils, etc., if they could actually get TO the leather. But the pigment dye is a protective sealer. It keeps the leather from getting stained from spills. It keeps the oils and conditioners out, too.

So, the redoubtable MNBox is right again! Save your money, boys, and use the dish detergent from the kitchen instead of buying leather conditioners at $20 a bottle.

I'd use Murphy's Oil Soap myself....