[Amanita]

I hope they don't go after 277 anytime soon, somehow I think it's a lot less likely a target than 270 Park Avenue or the Pfizer HQ.

What made 270 vulnerable was the fact that one company occupied and owned the entire building- since they are its sole occupant and owner, they can make a case for replacing it. In the case of 277 across the street, that's not the case, however. It's still owned by the company that built it back in 1964, and I suspect they're proud of it, it seems to be very well maintained. It's also a building with a diverse assortment of tenants and a pretty solid occupancy rate. (It will be even better when Chase moves some of its displaced workers in).

Being a fan of that building, I've done some looking around, and it looks like it's very recently had upgrades to its mechanical system, among other things. When I was in NYC, the area adjoining its main lobby looked to be going through renovations too- One of the cleaning ladies I was talking to said that the building was getting some upgrades to make that lobby area even nicer. So I think (And hope!) that 277 is planning to stick around awhile longer.

I don't know as much about 245- if that one were mine, I might look at a reclad to give it a fresh new look. I was looking through its official website last night, and it's a Brookfield building. They seem to be taking pretty good care of it, and keeping it up to date, in a similar fashion to 277.
However I'm not surprised to see Pfizer on the list- like 270 Park Avenue, it's owned and occupied by one company as far as I know, which makes it a target for the same reason.
425 Park Avenue had serious problems for a while before its partial takedown and rebuilding- it had an electrical fire several years ago, which it apparently never fully recovered from. I recall reading about how even years after the fire, extension cords were all over the place in some areas because the damage to the building's electrical systems was never fully repaired. That issue alone makes attracting tenants harder- they're certainly not going to want to pay as much as the management of a better kept building like 277 or 245 could ask for.