What kind of benefit are Bombardier claiming for the C-Series on a 200-300nm sector? Seeing as a lot of WX's routes are within this category, it'd be an interesting study. That said I can imagine Bombardier are getting a little concerned at the number of sales so I'm sure their sales team are getting creative with pricing, debt arrangements etc.
Here's a thought though......
If we firstly assume that CityJet are capable (and I believe they are) and secondly that they will be getting the C-Series then it'd be an interesting study to examine the business case for offering C-Series maintenance services under the CityJet / Air France Industries banner. The other variable in this equation is of course the Swiss (Lufthansa) order for 30 C-Series. They will undoubtedly be offering maintenance services to third parties via LHT on this type. The LHT issue withstanding, there may be a viable opportunity there.