I am an American who will be eating my way around Montreal for a few days next month. I want to avoid any Ugly American behavior possible and not arrogantly assume that everyone speaks English. My French is not very good, but I can pull it out when necessary, at least to show that I am making an effort to be respectful. I feel very ignorant for not knowing, but I haven't been able to find any resource that can answer my question honestly--the tourist board websites don't mention the language thing, presumably because they don't want to make potential tourists feel threatened.
So the question is, should I approach everyone in French and allow them to switch to English if they so choose--or do many Montreal residents actually speak English more often than French? I would really appreciate any advice that natives and previous visitors can give me.