I have over 1000 karma, and I've never seen it. I know it was given a quick trial after it was first announced, but from my surfing since then it doesn't seem to have been turned back on.
No. He activated it, but after a bunch of people complained, he turned it back off and said moderators could activate it again for special threads that they think need it (see https://news.ycombinator.com/item?id=7449857).