In Interviews^x, Idioms^x

I've noticed the American idiom "my bad!" meaning "it's my fault" or "my mistake" creeping into tv shows and magazine interviews. Is it a relatively new expression, or has it always been around? Why has it suddenly appeared on the radar?

You seem to be fascinated with the skills of non-native speakers vs. native speakers of English, Milky. Well, because this is formal written English with fairly standardized rules of grammar, I would probably choose the Professor. But remember, schooling isn't everything...that 15 year old could...

Dear Ayesha, I haven't heard about that college and I hope that it is a good college. Just my two cents : It means that what I said are just my 'views'. Others may have different opinions on the subject discussed and I'm just giving my views. Got it? I learned this idiom from this forum...

I am loving it is a popular / fashionable spoken idiom at the moment in UK - but you wouldn't use it in a job interview or any such formal context.