Had one of the best meals since I moved to Calgary a year ago. Mercato is serving up traditional Italian fare, prepared extremely well. If you decide to go, I strongly recommend going family style. There are lots of great items on the menu, and they are more than willing to allow you to share.
The menu is set up to be eaten in three courses. First is your antipasto, second is a pasta dish, and third is a protein. We started with the clams, which were cooked beautifully and served with fresh greenery to make it like a light salad. Next we had a risotto, which has surprisingly light and fresh. Last we had the halibut, which was cooked to perfection (which seems to be a rarity in Calgary).
The service was extremely competent. The allowed us to take our time and slowly enjoy are food and wine. We had a great dining experience. I would strongly recommend that people check it out again if they had a bad first experience.