Re CanCon: Like Steve, I'm not close to the industry, but I believe the rules have had a positive effect. It would be very tempting for radio stations to get their playlists out of LA or wherever and blindly follow whatever continental directives are laid down -- you can bet the US programmers aren't going to pay attention to unknown (to them) Canadians. At least somewhere along the line radio programmers in Canada have to be aware of Canadian performers.
Mind you, I get the impression that the criteria are pretty loose -- maybe someone who knows more about it can give us more details. Also, it would still be easy for programmers to fall back on the likes of Gordon Lightfoot, Shania Twain and Celine Dion. But I suspect people like those three wouldn't be where they are today if it weren't for CanCon.