Very upscale. Get the latest and greatest here. Items can be pricier as expected. You get what you pay for. Comparing with Eaton Centre, I seem to enjoy Eaton more than Yorkdale. It all depends on what stores you like to visit and if they have the collections that you are looking for. Also I happen to be at Yorkdale during the busiest times of the year so parking can take awhile. On the other hand, I find it easy to park at Eaton during the weekends - $8 for a full day.
At any rate, check online first if they have the stores you want to visit, call in to check if they have the stock if you can, so you can maximize your visit.
Overall, a very pleasant shopping experience.