I know some of the most spirited discussions on A.net are merger speculations however one analyst feels they are a bad idea, which I tend to agree.
IMO the most successful merging of operations are when assets are acquired not the entire airline. Very few airline mergers I think yielded the intended success, some notable exceptions being CO/People Express at Newark and DL at SLC. AA's TW merger has left STL a shell of it's former self and gave them very few intenational authorities that are in use today. And of course their merger with QQ and Aircal has been adressed ad naseum.