Right now things on AA are "bundled" for the most part. When you buy a ticket, you get the transportation, EQP/EQM/RDM (as appropriate), whatever meal may be due, etc. In unbundling, there would be a base charge, with add on charges for earning miles, getting meals (maybe premium meals as well). This is the basic idea, and I'm sure that there are other items that can be thrown into the mix as well.

Cheers.