First off, I want to thank everyone who left informative comments on my Hiatus post. (I should add that wolfangel was quite correct that people would often switch to English when they heard I wasn’t a native speaker, but I got a fair amount of French conversation in anyway.) I learned the word dépanneur ‘convenience store’; I heard the affricated d and t; I did not notice the tense/lax vowels or the -tu questions; I did notice the contractions (chais &c) and a feature nobody mentioned in the comments, the raising of nasalized vowels: vent sounded almost like vin (with /æ/ as in hat), and vin had a high [e] and sounded diphthongized ([veiN]) — in fact, one guy said matin so that it struck my ears as [matiN]. In general, men spoke with heavier dialect than women, and some of them were virtually incomprehensible.
We spent our time mostly in the francophone area north and east of our hotel, so we dealt with a lot of French-speakers, but all of them were willing to accommodate my non-francophone wife except for one Metro ticket-seller who answered her “Do you speak English?” with a brusque “Non.” People seemed by and large bilingual; a striking example of this occurred during our dinner at the (very good) Bistro Côté Soleil on rue St-Denis, when we sat next to two women, the younger probably a grad student in art and the older perhaps her faculty advisor. The younger spoke almost entirely in French and the older almost entirely in English, but they clearly understood each other perfectly and occasionally dropped into the other’s language (both had fairly heavy accents). Other people switched back and forth in the course of a few sentences. I’ve been in many multilingual cities and some with a very widespread minority language (often Spanish in the US), but never one where two languages met on such equal terms. Whatever contortions Québec has had to go through to get where it is today, I’m impressed with the result.