Yup, I didn't manage to get a screenshot of him out of all the excitement and scrambling, but I did get one of the text at the top where it says "Diablo walks the Earth" while I was talking to Ormus in the Kurast Docks. I know a couple people who've seen him several times a day, but I've only seen him once, so I don't know if they're being completely honest with me.
I've seen screenshots of him in red and green, but when we spawned him in Travincial, he was green. I still remember that much without taking any screenshots.
The SOJ counter was going off every couple seconds instead of every few minutes, and it became increasingly frequent before he finally appeared. The ground shook and then the text appeared at the top signifying his arrival.
He won't escape us next time. RAWR!!