Of course, we all are guilty of engaging in this--myself included--but I like to think I do it less than others, because I try to be thoughtful.
http://www.nytimes.com/2012/12/02/fashion/bah-humblebrag-the-unfortunate-rise-of-false-humility.html?pagewanted=all
Broadway Legend Joined: 3/4/04
"It's called a complisult. Part compliment, part insult. He invented them. I coined the term. See what I just did there? That was an explainabrag."
One of the people cited by the article is a Broadway actress:
On the overworked front, we’ve heard from the Broadway actress Kerry Butler (“I’ve been signing so many autographs lately, that I was writing a card to my dad and started to write my last name!!”)...
The book looks like fun:

Humblebrag: The Art of False Modesty by Harris Wittels
I didn't read the whole thing because I'm making dinner, but honestly if I got into a fender bender with Dane Cook I don't even think I would recognize him.
My friend was at a restaurant in Norfolk, VA one time and Taylor Hicks (American Idol/Grease) was in there and they had no idea who he was. They asked him to take their picture for them, and he was shocked that they didn't want HIS picture. BAHAHAHA
Anyhoo, that book does look fun!
Broadway Legend Joined: 9/16/07
I prefer the term 30 Rock coined for this action several years ago--the "backdoor brag." Seriously, though, I have an acquaintance (a moderately successful writer) who is a master of this. He was recently nominated for the same fairly prestigious award by two different magazines, and he started a Facebook post announcing it by writing "Maybe there IS such a thing as too much good news..." It was all I could do not to unfriend him right there.
Love that term.
Broadway Legend Joined: 10/18/04
"Oooh, Kerry Butler got called out!"
She is permanently, positively punished.
I'm too modest to open a thread such as this.
And, even if I wasn't, I'd never be so conceited as to post.
This whole phenomenon--as well as the other, more/less egregious forms of self-promotion described in the NYT article--seem to me the essential underpinning of the Twitter concept.
In order to believe that the universe wants constant updates on your every trivial thought, one needs the kind of outlandishly inflated self-regard that leads, inevitably, to pathological bragging--humble or otherwise.
I have a facebook friend who posts a lot about how awesome his life is, and he usually namedrops because he works with famous people sometimes. It's always, "Wow! So amazed to have been involved with this project that is gathering so much Oscar buzz" or "My wife is so completely beautiful--thank you for 4 years of sooo much bliss!!!" I mean, after a while you start to wonder what this person is trying to conceal or overcompensate for, unless he really is that insanely happy all the time, in which case why is he documenting every "feels" on facebook?
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