If the messenger hangout is the same as when i rode there then PVM (place ville marie University between Rene Leveque and St Catherine) is the place to go to hook into the messers scene, or just ask. As for bars, it's been way too long so I haven't the foggiest. Bike culture is alive and well in MTL, I was just there this week and loads of folks riding around.... some nice fixies too. With the mountain in the middle of the city and the real mountains north and south city,the terrible roads and real snow in the winter, MTBs just make sense. Bromont in the south was the venue for the MTB World's so there are some killer trails for that.