Originally Posted by toddbishop
Unless you're talking about someone under the age of, say, 14, it's pretty offensive, especially in the context of a conversation about “girls” being crappy drummers who unfairly hog all the YouTube hits. It's not a whole lot better than calling an adult African-American male “boy”— there's the same ongoing history of belittling there. To people like our Jasper, this is an example of political correctness gone mad, but it's really just acting like a grown-up and treating people with basic human respect.
Doesn't really ring true in the UK. Boys and Girls are 'usually' the term for children but there is no sense of offence if it's used for adults.