As of January 1, 2006, the newly created "merged" City of Montreal is made up of 19 boroughs. The remaining 13 boroughs retain their independence. The link below leads to a map where you will see that the City of Montreal boroughs are orange and the independent boroughs are yellow.
Each borough/neighbourhood retains a distinct character and history. Here are links to each of them:
The City of Montreal's website has lots of information about the 19 boroughs that make up the City of Montreal)