MEDIOCRE at best.
We checked in at 2 pm and left our bags returning shortly after 5 pm. Finally they secured a room. We were reserved for a King Superior and asked if there were any Hilton Honors upgrades. We received the standard lines from Fevan, such has "it will be a lovely room" and "I'm sorry we're FULLY committed". In other words, there's not a chance you're being upgraded. She gave me a King Superior room 803 which overlooked a construction site, with a promise that if anything became available she would call the next day. Of course we never heard from her again. After we got to our room I called the front desk and asked for a manager to come up and appraise our view. The front desk said that would not be necessary and we would be moved the next day. We also had to call for the luggage, they just left it until we arrived in the room several hours later. 
The next day, we were told to have our bags packed and ready by NOON and the hotel would automatically move them. The next day we were ready as promised. At noon, the front desk said, "oh we're working on it. Do you have anything to do this afternoon?" In other words, nothing had been done.
We went to a matinee and came back around 5 pm. Still no room and another big hussle to find a room, only to receive an "upgrade". We shold have demanded to view it first. We received an "upgrade" to a one bedroom Suite 17A. It hasn't been remodeled in years. tattered carpets, old furnishings. In the bathroom there was a heating unit in the wall that had of all things masking tape in double and triple runs taping it on all four sides to the wall so that it would not fall out. What kind of management team would allow maintenance to pull that stunt? In addition a lamp was broken at check in. Since it was already late we had them come up and fix it the next morning. We did not request another room change because we were completely over the hotel and the nerve of the front desk to shove us into this room. 
We received a bottle of Champagne and fruit/cheese plate from our company. Besides the cheese and one full apple there was a "sprig" of four grapes. Why bother? Was our cheese and fruit plate the one that got the last of the grapes? I'm sure that cost my company a fortune so why don't you put some effort and quality into it. Had it not been left in the room I would have called and asked for a new one to be brought up. Except, the wait would have been excruciating. 
It was a wasted four night stay. In general, people from all over the world visit New York City and many of them will splurge to stay at the "historic" Waldorf Astoria. They certainly fulfill the "historic" part of the equation. Quality is another issue. The hotel is filled with tourist buses of guests who stay here because of its iconic history. My group stayed here and it cost a fortune. Our one dinner was fine, no problems and the servers in the banquet department are excellent. Breakfasts were fine but the buffets for the most part were all exactly the same. The public rooms are beautiful and have been redone. The Grand Ballroom and the 18th floor dining room and meeting rooms are also stunning. 
We have stayed twice previously in the Waldorf Towers and had no problems. Our rooms were nice and once we were upgraded to a suite. But our experience this time was horrible. I could have easily demanded satisfaction and I would have eventually forced a response, but after the delays and run around with the first room change, we had no hope in the ability of the front desk personnel or their managers to succeed. They were indifferent at best.
I'm in New York for meetings at least 4 times a year. There are so many great hotels that are within a few blocks of the Waldorf for guests to stay. No one needs to go through what we experienced. I get the feeling that many of the people who have written reviews are tourists coming for a special occasion that want the history a big 1000 plus room tourist hotel can provide. If you want to be part of the rat race, one might as well stay at the Marriott Marquis on Times Sqaure with their hordes of tourists. Actually the rooms and service are probably better. As I said, we will not come back, even to stay on the Towers side. I'm in hotel rooms 50-75 nights/year and this is the worst stay I can remember.