When HSR trains (MTO EA starts this fall?) stop somewhere along the Georgetown corridor and require a people mover extended to it, and normal GO trains also happen to stop at that station and intercepting Eglinton and Bloor lines, any money extending Eglinton to the airport looks a lot less appealing. This is doubly true if the fare integration question is answered in a meaningful way.
I figure that Eglinton extension to the airport will disappear from the plans around 2017. A Finch extension, however, still has a business case.
Smart Track may morph into a westward extension of Eglinton, but I don't think it'll go to the airport. Pure speculation of how the politics will play out, of course.