Downtown Chinatown is no longer the mecca for Dim Sum or those other Cantonese eatries. In fact, many businesses are now selling Vietnamese Pho's and bakeries. Immigrants from Vietnam, Indochina, and many newly ones from Mainland China have taken over this area (Dundas/Spadina). I very seldomly visit the place.
The mecca for Dim Sum, Noodles, HK Cafes, etc are in Markham, Scarborough, Richmond Hill to the northern suburbs and Mississauga to the Western Suburbs. And these places are really catered to the local Chinese such as myself as oppose to the tourist.