Msn,
I do believe money talks as you said..

I think Airbus is very much entrenched in Air Canada. Airline is already operating A319, A320, A321, A343, and A333s. A345s and A346s will be coming into the fleet as well. I do see AC being a very good candidate for an airline going to an all airbus fleet, if Airbus can develop a replacement for the B767-300ERs.

I think Boeing's problem with the B717-200 is, it is a plane which came from the MD. (The MD95)

There is bad blood between the Boeing and MD workers like AC and CP..
And the B717-200 competing with the B737-600 directly also does not help.

Also depends on, how much power LH will have in the order as it is a joint STAR order and LH will likely be the airline ordering the most jets. I am sure Airbus will be trying to scure customers for the lessor who have ordered the A318s. So it is also very likely. But I suspect, it could go either way to Boeing or Airbus or even bombardier...