If AC approves the Onex deal, the combined airline will be called "Air Canada" and be in Oneworld. I guess that's were the 15% AMR stake comes into play.

See http://www.cdnair.ca/eng/cpi/01discover/onexcacdn.html

Extract:

"We strongly believe Canadian Plus members will benefit in a number of ways

- The new airline will guarantee your Canadian Plus points.
- The new airline will become a member of the oneworld global alliance of world-leading airlines including American Airlines, British Airways, Cathay Pacific, Qantas Airways, Iberia and Finnair.
- The new airline will continue to rely on serving the business customer as a key component of its strategy to build revenues and ensure the stability and growth of the industry.
- Canada’s communities will benefit through the preservation over the long-term of thousands of jobs, which are at risk if Canada’s airline industry continues to decline
- A strong Canadian carrier will mean improved service, a better choice of flights on many routes and more non-stop flights to more destinations, including more international destinations."