Manhattan's population density is amazing. The closest Toronto gets is the downtown core:
This area is about 1/5 the size of Manhattan (4.5 square miles) and had 175,064 people in 2011, up from 132,434 in 2006. Population density is 38,903 people/square mile. The population would need to reach roughly 320,000 to match Manhattan density. Toronto's downtown core population continues to surge, but it will take a generation to reach Manhattan density levels.