Jon, as I think from your second post, I wasn't criticising the attitude (which I took to be jokey, even without the little picture), but the language drift.

Words change and get new meanings and abandon old ones. I'm not sure how widespread this one is, in a world language. That's the kind of thing the Mudcat can help determine.

My understanding is that, where the scorn meaning has crept in, it's used alongside the older meaning, and who knows which will win out - I suspect that it'll turn out to be a passing fad. I think saying "sad" in the scornful sense will soon date people as much as saying "groovy" would.

And the reason for that is that it doesn't really meet a real need - in this it differs from gay. There isn't a group of people who are fed up with being called pitiful or whatever, and would prefer to be called sad. And on the other hand there are a lot of people who still use sad in the meaning of unhappy, and won't relinquish it easily.

Of course sad has an earlier meaning still, which was more or less equivalent to "serious". Words change.