Toronto's waterfront is full of diverse communities with residences, hotels, offices, parks, public squares, schools, museums, community centres, swimming pools, boating schools, tv and radio studios, recreational activities, concert venues, theatre, art galleries, restaurants and stores. (all south of the highway) East of Chicago's lakefront highway, you mostly have a cement promenade, parks and beaches. Besides Navy Pier and the zoo, there ain't much else, except for a few isolated restaurants on the beach. There just isn't much to do besides sun tanning on Chicago's lake. Toronto's waterfront is much more integrated into the city, while Chicago's is very separate from it. To cross that highway, you have to wait forever for the light to turn green. (near Millennium Park)
Another thing I like about Toronto's waterfront is it's not straight up and down, like Chicago's. Toronto's shoreline is much more interesting with quays, curves and all kinds of parts that go everywhere. It takes much longer to explore and get to know. It's full of surprises and has lots of hidden places. You can't find that in Chicago. It gives you way more options and is much more diverse. Think of how different every part is, with crowded areas and completely deserted sections. Chicago's waterfront has no charming neighbourhoods like Ward's Island or the Beaches, nor can you find the kind of atmosphere you have there. It doesn't have interesting landforms like the Scarborough Bluffs. Chicago may have that great skyline, which can be seen from the lake but the actual waterfront, east of the highway, just isn't all that interesting or diverse.
Another thing about Toronto's waterfront, is that it's not even finished, so it's just going to get more interesting and better, with time. It may have taken us a long time to get our act together but I think it is worth the wait.