Good location and nice staff
The hotel is well located. I took a bus from NYC to Boston and got to South Station. 5 minutes walk from there. 
Front door man was very welcoming and friendly as the people at the front desk.
My room was on a high floor (forgot which one) so I had a nice open view. The room looked like the other Hyatt's, it was clean, well proportioned and quiet. 
You have free wi-fi for a limited period, which is better than other hotels that would charge you for that.
If you don't have a map and are trying to find the hotel, don't ask for the street name, ask for the Hyatt. It will be easier for people to direct you there.
I did not request it but I saw there was a hotel person at the lobby/bar who was advising other guests on where to go and what to visit while in Boston. He sounded really nice and helpful and prepare them a whole plan for their one day visit. I thought that was nice, he took the time to seat with them and do it.
I would stay here again.