They did a sequel a few years later, in 1982, and this is that show's opening number. It's not nearly as special as the Broadway medley, but it's still very enjoyable for all the performers who participate. This is a medley of songs about New York City. Also, several of the entertainers get to sing much longer than the few lines in the previous video.
A slight "warning." Before the medley begins, there is quite an awful opening song. So, you might want to jump directly to 4:30 when the medley starts. But -- my recommendation is to not do that. A few stars show up in the opening number, and there is a really fun moment at 3:20 when one particular star appears. I suspect most people won't recognize her right away, but wait a bit, and they identify her on screen. (She also appears in the opening sketch, but it's among a group of people, so it might be even easier to miss.)
There's also a very clever combination of songs (from "West Side Story") with one performer, which comes at the 13:00 mark. Even though he's not a singer, who he is makes for a very smart and fun moment. Some people today might miss the joke, but I think most people who were around at the time will get it even 30 years later.