I just rewatched this the other night (it's on HBO, but only until like the 31st)!
It's the closest we have to a gay Titanic.
The acting is great, as is the script, the cinematography, the writing. Just all of it.
One of the things I love about it is that it has no real political undertones, as most big gay films (Philadelphia, Milk, The Danish Girl, etc) do. I think that Carol is like it in that regard.