I agree. It's very much overused.
WAIA and the other "lines" and catchphrases were originally intended for use in Real Life situations where people needed a quick, neutral reply to shut down a nosy line of questioning or presumptuous statement.
On a message board, where there is plenty of time to read the message, ponder its intent, and formulate a reply in their own words, those same lines come off as trite, flip, and childish - like a middle schooler trying to get an, "ooohhh, buurrnnn!" reaction from classmates.
I don't mind it so much when people do it a joking manner - I've done that myself - but it irritates the snot out of me when it's used as part of a serious reply.