Hey Bean, lemme be the first to weigh in with newbieness to this word (or, um, can't think how else to phrase this!): I'd never heard it before. Don't think I would've figured it out from the context but now I now what it means, it does make sense.

I like it as a word, but it somehow sounds more jolly and friendly than it "should" (ie, for what it connotes). It sounds so close to marksmanship or some other more sporting notion....But I guess if we have "war games," then "brinkmanship" (or "brinksmanship") is sadly appropriate....

Tanks fer the new werd, anyway!