Visiting wonderful NYC again in September after break of 3 years. Are there any great 'changes' for us over 60's tourists? Hoping to stay in either Peninsular, Casablanca, Michelangelo or Residence. Has anyone any experience of these hotels?

As for something new, put The High Line at the top of your lists. It provides you a view of New York from an sort-of on-high viewpoint. Situated on former freight train tracks, running from Gansevoort St. to 34th St., between 10th & 11th Aves., you really view the city from a different perspective.
For more details, do a google search of The High Line.

Please be aware that the climb to the High Line is approxiamtely three stories of stairs.

If you are interested in architecture there are many new glass structures that undulate and create visual curiosities. These include the new building at Cooper Union and the Gehry residence on Spruce Street just below the Brooklyn Bridge.

There is an elevator to the high line near the Chelsea Market and by the time you show up the next piece of it might be open.

The World Trade Center Site will look a lot different.

thestarryeye.typepad.com/explorenyc

Michelangelo is WONDERFUL. Recently refurbished and the owner's wife picks all of the interior design elements with impeccable taste. Their restaurant is divine. Stay there if you can. September is very expensive as it's the UN conference so hotels all over midtown book up very quickly. All that to say..stay at the Michelangelo and book your room NOW.

I've stayed at the Residence Inn frequently in the past few months. I'm fussy about hotels and I like it lot. It's clean, everything is in good repair, and the staff is nice. The rooms have a microwave and small refrigerator. The Times Square area can be hectic of course, but the hotel is quiet inside.