I'm starting this thread in the hopes that Host Dan may allow this to become a sticky. It is difficult to keep track of which airline is being used and in what part of the world. For instance, United was Regent's choice in South America. This is apparently no longer the case (at least not from Rio to Miami, Dallas or Vancouver). They are using Delta and U.S. Air.   I learned last month (March, 2013) that, in addition to a deviation fee, if you opt for American Airlines in South America,