It seems that it doesn't matter where you go, at any one point you can see a spire. I'm sure outside the immediate city centre its maybe not like that, however in the downtown/old montreal area, at one point I could spin on the spot and see five. It is indeed a very catholic city.
Everyone had also told me how beautiful Montreal was and that was also true. It is so very European (the french should have been a dead give away I guess) and while the French Canadians are very proud to be offshore Francophones, english is spoken everywhere and its very easy to get around.
Old Montreal is a great day out. I wandered around, went to a few galleries, an exhibition on Agatha Christie (which was actually really good) tried the famous Poutine (not really a fan) and visited the Notre Dame basilica of course.
China Town is great for food as is the latin quarter and if you really want to blow your mind, head underground to the kilometers of shopping that is hidden under the city streets.
It was a great 4 or 5 hours walking the streets, checking out the architecture and enjoying the cold but clear day.
Overall Montreal was lovely and I walked, ate, sat in coffee shops, did museums and galleries and felt very cultured by the end of it all. Very cultured indeed.