I've stayed in alot of hotels in Beijing, but the Park Hyatt is worth writing a review about.
The rooms are minimalist and understated, but very modern and elegant. Probably one of the largest bathrooms I've ever seen in a standard room - with a very deep Japanese style bath. The bathroom flowed easily into the main bedroom area. Decent sized closet and very comfortable bed.
The hotel staff went out of their way to keep me informed about my lost luggage at the airport, with several written messages updating me when it was located, when it had left Hong Kong, when it arrived in Beijing, and when it would be delivered. I was very grateful.
The food at China Grill and drinks at China Bar on the top floors were great. The Xiu bar downstairs was interesting to have a peek, but too crowded for my taste - make sure you flash your key card to get priority access so you don't have to queue to get in. Its one of those 'it' places to be seen.
The pool and fitness centre were WELL above most hotel standards.
I was very impressed.