Upper Canada Mall is absolutely awesome for strolling around with a baby. The aisles are wide, the mall itself is not busy, the babies r us has HUGE selection (Better than the Richmond Hill store in my opinion) and there are three nursing rooms just on the second level! The only down side is that the mall elevator is kind of hard to locate...we walked pass it twice before actually finding it! (But you can always use the elevators in the department stores)
There is a nursing room in the food court on the second level, as well as one in the children's play area (outside babies r us) and of course Babies R Us has their own mother's room as well.
The mall's nursing rooms are both equipped with a TV...the sound is on very low so you can't really hear it..but the light itself is enough distraction for my baby... so if you have a fuzzy eater like me...it may be tough to get them to focus on feeding...other than that, the rooms are spacious and well equipped =)