Let me take a contrarian point of view here, at least as far as AM in Quebec is concerned:
It's dead, Jim.
(I always wanted to find a way to work that into a response to my good friend Mr. Pastrick!
There is effectively no AM listenership in Quebec outside Montreal - and indeed, only a tiny handful of AM signals remaining at all, most notably CHRC 800 in Quebec City, which struggles to survive with a French-language sports format. There is no AM at all in the other sizable metro areas: Trois-Rivieres, Sherbrooke, Saguenay, etc.
Within Montreal, there were two AM stations serving the Francophone community, and according to the most recent BBM numbers, CINW barely registered, pulling just a 1.1 share. Its all-sports sister, CKAC 730, did a little better, in the 5-share region, but still far behind the big FMs. Corus very shrewdly moved its news-talk franchise to FM a few years ago, launching CHMP 98.5, which is now the #2 station in French Montreal.
It's not impossible for a new entrant to come to the table on 690, but they'd have to make a case to the CRTC that they could profitably operate an AM signal in a market that has moved very decisively to FM. I think that would be a hard case to make these days. You have to have a pretty mainstream format with decent ratings to sustain the high cost of operating a 50 kW AM signal, which makes 690 undesirable for any of the smaller ethnic broadcasters like CJRS that now struggle at the top of the dial.
On the English side of the equation, CINW barely registered (2.6 in the last BBM toplines) against one of the last really successful AMs in Canada. Astral's CJAD 800 is a monster - not just the #1 AM in Anglo Montreal but the #1 station of any kind, with a whopping 26.3 share in the last BBMs. This, incidentally, is why CJAD didn't apply for 940 the last time it was available and why they're unlikely to do so now: they cover the market just fine where they are, and have no reason whatsoever to move. It is, quite simply, the last viable AM remaining in the province, and one of perhaps a dozen in any major/medium Canadian market. (A few more, off the top of my head: CFRB, CFTR, 590 and maybe 640 in Toronto; CHML in Hamilton; CKNW and CKWX in Vancouver; CHED in Edmonton; CJOB in Winnipeg; CHQR in Calgary; maybe CFAX in Victoria.)
Anglo Montreal is shrinking fast, now well under a million population and soon to fall behind Ottawa if trends continue. Would the CRTC even approve another entrant in the market if someone wanted to reactivate 940? It seems unlikely to me.
While there's still some life left in the medium, as CJAD indicates, the death rattles are setting in.