Dieu du Ciel! and take the short trip to Chambly, visit the fort & Bedodaine. Oh yeah and the tittie bars on St. Catherine Street.
Like youbrewidrink said, Dieu du Ciel! is a must. L'Amère à boire is another great spot for exceptional lagers. Benelux, nice brewpub (special cask beer every Thursday). This tool can help too. Enjoy your stay!
When are you coming? There's Le Mondial coming end of May. Check out Succursale & L'Espace Public, two up-and-coming brewpubs that make some solid brews. seblp nailed the main stores to hit. The 2 beers that i continually encourage people to grab are these, very good: http://beeradvocate.com/beer/profile/13905/77207 http://beeradvocate.com/beer/profile/18003/62986 Recent releases by Dunham are pretty solid as well.
I too will be in Montreal with my wife (Jan. 25-28), and then staying a few extra days for work (until Jan. 30). Thanks for the tips. Plan on taking advantage of the suggestions!! Thanks!
Vices et Versa is also a nice little bar that has a ton of local beer on tap. You can see on their site what's available, although here on BA there are so few reviews of the quebec stuff that you'll have to decide on your own what to have
Brouhaha broue pub have amazing beer too if you got a chance to go there http://brouepubbrouhaha.com/index.cfm