The soap-opera that is NBC's late-night programming and who will get to host what show and when will impact television in Canada as well.
Jay Leno's soon-to-be-cancelled prime-time variety/talk show has been seen on the City TV stations at 10 P.M. (meaning that in Toronto and Vancouver, they've been simulcast on City at the same time they've been seen on NBC stations over-the-border), while the Conan O'Brien and Jimmy Fallon shows are currently seen on "A" (once known as "A-Channel") at 11:30 P.M. and 12:30 A.M. respectively. Again, in the Eastern and Pacific time zones, these are simulcasts with NBC's over-the-border stations.
City will face the biggest problem with losing Leno, having to fill five prime-time hours a week. Given the state of Canadian television, Leno would probably have to be replaced with a simulcast of a U.S. network program. But which ones?? It will be interesting to see what City does.
I believe CITY-57 in Toronto is the only City station that still has a decent-sized news department; if all the City stations still had comparable news departments, I could have seen them move their late local newscasts to 10 P.M., but that would place them in competition against CBC's "The National". Still, local news on CITY Toronto could be the best alternative for CITY in the 10 P.M. hour, and would probably draw far more viewers than "National" on CBC flagship CBLT-5; but might not do as well as entertainment programs on other stations, most notably CTV flagship CFTO-9.
The solution outlined in the last paragraph would only solve the problem in Toronto, and not the other City markets.
For "A", they could very well continue to simulcast NBC's late-night lineup from 11:30 P.M. onward, regardless of who hosts.