“Good for you”, old-fashioned but otherwise sincere.
I’m American.
(Reading the other replies, I agree with those who say: Of course, you can employ it sarcastically, just as you can employ “Good for you!” sarcastically, and the out-of-date wording of the phrase plays into that. Still, I wouldn’t yet say its primary meaning is in that snarky deployment. To put it another way, I don’t think the phrase itself is that restricted in tone; its tone is whatever tone it’s used with.)
[Hm, but the more I think about it, maybe it is restricted… I can’t bring myself to imagine saying it in any other non-contrived case but the sarcastic one. Of course, originally, those words were mundanely sincere, but I guess now, maybe they are primarily snarky.]
Ditto. I know the phrase once had a non-sarcastic use, but I think the sarcastic use is now the dominant one, at least in the US.
I’m also an American.
I have never heard it said without sarcasm. I of course think of TR, but I don’t think it’s been said sincerely since. I’m American.
“That’s great news for you!”, but it can be (and often is) with sarcastic intent.
American
Exactly what he said.
It sounds very old-fashioned to me.
A direct replacement for good for you. The delivery gives the meaning you think it is good, or you’re being sarcastic.
Can’t recall any use of the word in everyday conversation or in the news, except in the phrase “bully pulpit”. I don’t really know what that’s supposed to mean, either.
Good for you in a sarcastic way, usually. I’ve never heard anyone use it in a sincere context.
Florida, US
I don’t recall hearing anyone use the phrase in a long time, and it’s interesting that in many places throughout the world this old-fashioned expression lives on with a mostly snarky connotation.
I suppose the word “swell” has evolved similarly. While it was possible to use it earnestly from the 1920s through the 1950s, from the '60s on it fell out of fashion. Now one can hardly think of it being used without a simultaneous rolling of the eyes.
Except for me. I started using “swell” sincerely sometime in the late 1980s. And if I thought of it, I might say “Bully” non sarcastically, too. I like old usages like that.
My Webster’s New Twentieth Century Dictionary (2nd Ed.) gives two definitions for the adjectival form of “bully”:
- Dashing; gallant; as my bully boy.
- First-rate; fine [colloq.]
It is in the second sense that TR spoke of the presidency as a “bully pulpit”: it’s a very good way to get people’s attention.
It seems as though many people, not knowing this sense of the word, have assumed that he meant it in the more common sense of bully: “a person who hurts, frightens, threatens, or terrorizes over those who are smaller or weaker.” So much so that now you occasionally see writers using “bully pulpit” to describe a politician or other powerful person who uses bullying tactics.
Obviously, such people exist and the phrase accurately describes them in a rather clever twist on the phrase’s original meaning. But many people, unaware of the colloquial usage, may confuse the two very different meanings of the phrase and read the wrong meaning into the more innocent uses.
‘Good for you.’
IME it’s usually meant sarcastically. Depends on the delivery.
Ditto and as **Marley23 **mentioned Arsenic and Old Lace, it is worth adding that the reason Bully is used in the play and movie is the Uncle thinks he is Roosevelt.
American from New Jersey.
Yes. And I didn’t play Teddy, by the way. My dad didn’t see fit to quote any of my lines. 
Forgot to mention it in my last post, but I’m from New York.
“Good for you” or “How nice for you.” I’ve never heard it said without sarcasm, so it surprises me that some people use it sincerely.
NH, US
English
“You’re clearly excited by this, but I’m not (or perhaps I think you don’t really deserve it)”
Similar in usage to Whoopee shit.
It’s a sarcastic phrase meaning good for you but things suck on my end. Northeast US.
“Well, aren’t you feeling proud of yourself (for a not very noteworthy event.)”
American, southern US if it matters.
I’ve always had the impression it was a sarcastic “Well good for you” or something along those lines. I’ve never heard it in real life but as a child I read it in Caddie Woodlawn. I’m American, from Ohio BTW.
I never knew the phrase to have a sarcastic bent, but I know it as 19th-century for “well done!” (I imagine Teddy Roosevelt and other old rich dudes would say this.) Also old rich British dudes. I’ve never heard someone use it except in a joking manner, but it still means “good for you.” Never heard it used sarcastically.
American.