Having stayed in NYC at least 50 different times from the Ritz in Battery Park, many trendy hotels, and most of the "upper end large hotels", this is our favorite.
The Pierre's location is perfect. Close enough to mid town, but away from all the concrete and noise. Being across the street from Central Park helps a lot. The most upscale shopping in the country is very convenient as well.
The lobby is subdued and stately. The restaurant (Sirio) is exceptional for a hotel. The workout facitliy is small but very well done. Our room was most likely the least expensive and small, but still very nice.
What is truly exceptional though is the service. The special touch of a "manned" elevator is unique as they always greet you with a smile and make you feel appreciated. But the tone of excellent service is consistent from room service to maids to concierege to bellman.
If I'm traveling solo on business I'm not sure I'd do it as Hotwire works for "get into the city, do the job and get out".
But if I'm taking my wire and want to really be pampered in what we now consider to be our top choice in NYC......it's the Pierre.