There are a few different Hyatt hotels in the area and I almost left a review for the Hyatt Place hotel until I check the address, so make sure you are reading about the correct hotel.
As for this Hyatt, right next to the airport in a business complex, it was great. Very nice inside; clean, spacious rooms; and nice staff. I read the review about the pocket doors in the bathroom, in the two rooms we had, both had normal hinged doors. It's a suite style room with a bed on one side, half divider with a flat screen TV, and then a sitting area side with a couch, love seat and desk/chair (check out pics from other members). There is $5 bottles of water and free coffee in the rooms with Travel cups (that's nice for the morning rush). We didn't use the bar area in the lobby but it looked nice and had a small selection of pastries. There is a nice Koi pond in the lobby with some pretty impressively sized fish.
If you don't have a car, there isn't too much in the immediate area (it's a corporate center). But about a mile away there are a few shopping centers with fast food and restaurants (Wendy's, Taco Bell, Fridays, Bertuccis, etc) and we stopped at the 7-11 to get a few drinks and snacks.
We used the hotel for one night before an early morning flight from Dulles. The beds were nice and it was a quality hotel. The free shuttle starts at 5:15 and ran every 30minutes, and at 6:45 he was right on time. I would definitely recommend this hotel for people flying in and out of Dulles airport.