OthmarAmmann
Omnishambles
The Bruins and Rangers may have been around longer but for the most part, if my understanding of NHL history is correct, they were both largely irrelevant for much of the pre-expansion era. Rivalries and perception levels are largely based on relevance- because of the Yankees success in MLB people in Boston have always had a reason to hate them and because of the Celtics success in the NBA people in New York have always had a reason to hate the Celtics. With the Canadiens, Maple Leafs and Red Wings winning everything in the NHL, there was never a reason for people in either New York or Boston to hate or really even care about the other.
If anything, considering that pro sports in the US have basically always revolved around New York and Boston (and Chicago and LA to a much lesser extent), the fact that neither the Rangers or the Bruins are the NHL's "glamour" franchise probably has a lot to do with the league's stature on the larger sports landscape. There's no way to prove it but I dare say that if the Rangers had been winning Stanley Cup after Stanley Cup in the 40s, 50s and 60s, hockey would be held in a much different regard all over the US than it actually is.
Well its not like the NFL is at the bottom of the heap because neither the Jets nor the Pats existed in the pre-expansion era. Anyway, I only threw Spike out as an example. If anybody wants to believe that the NHL holds better than #6 in this O6 market than they're free to do so (although I'd appreciate a PM so that I could arrange the sale of a certain bridge).