I had a colleague who had stayed there and called it one of the best Marriott hotels he's ever stated at, so when business had me going up to Toronto, gave it a shot. Have to say he was right on. Private parking in a garage that is next to the hotel, a huge, modern and spacious lobby.

Rooms are very modern and spacious, clean and comfortable. Plenty of outlets including USB to plug into. Could not hear anyone else (had two colleagues who said the same).

Gym is very large and modern, also has indoor pool and changing rooms.

Has a bar / restaurant that is above a typical hotel menu, friendly staff.
Ruth's Chris Steakhouse is also attached to the hotel for another dining option, movie theatre across the street and a number of other restaurants. Close to the 407 so convenient for getting around.

Would recommend and stay there again. Also very reasonably priced.

Our recent stay at the Toronto Marriott Markham was easily one of the best hotel stays we've had, and we've done quite a bit of travelling.  We spent 4 nights at the property attending a funeral for a close relative.  When I notified the staff of our reason for coming, they really exhibited a level of customer service that was refreshing.  We received a condolence card signed by the team, they provided a few cards towards shared appetizers in their Draco restaurant, and they even sent up a nice fruit plate to the room.  They also lowered the nightly parking cost for us.  Since I always forget staff names, I have to shout out Ami who was working at the front desk.  She was the nicest most pleasant person we've encountered during our travels.  Most importantly, when she greeted our family when we returned to the property, it actually seemed genuine.  I hope this property knows what they have with her and doesn't allow her to escape :)

The property itself was wonderful.  Still fairly new and in an area that still under development.  There is an adjacent parking garage.  Parking is normally $20 CAD per night.  You just need to keep the card the machine provides you on your first entrance as you'll need to feed that same card into the machine as you come and go.  Remember to capture a shot of your license plate when you arrive to provide to the hotel staff.  Parking is pretty smooth.  Parking for the hotel is on level 3, 4 or 5. Unfortunately, the parking garage isn't connected directly to the hotel, so you'll have to grab the elevator down to the G level and walk across to the property while trying no to freeze to death.  

The room was well lit and spacious.  For the frequent travelers out there, there are plenty of outlets all over the place and water pressure is solid.  We stayed on the M Club (4th) floor.  The M Club lounge came in very handy on a few morning for breakfast.  They had a decent spread of meats, fruits, toast, juices, coffee and tea.  We also stopped in a few times  to grab some bottles of water for the room.  My wife visited the gym which she said was incredibly spacious.  We did not use the pool during our stay.  When you have a hotel stay this good, you just HOPE that once the local area is fully developed and the influx begins, they're able to maintain the level of service they displayed.  When in Toronto again, I would stay here in a heartbeat.  Marriott has a gem with this one.  Phenomenal stay, property and people.