One area that is important is what will change (versus discussing speculation on whether there will be a deal or not), if anything, in terms of frequent flier programs, hubs, alliances, etc. This seems to be something where everyone is speculating but there are some answers out there.
I found two good FAQs on this
American-US Airways Merger: What Frequent Fliers Need to Know
Clearly, more info will be trickling out as a possible merger announcement approaches but, despite the momentum, nothing is set in stone.
[Edited 2013-02-07 21:44:00]