Holy shit. The article is not even entirely correct - he was teaching classes as recently as 3:15 this afternoon, when I took his CS154 final. I saw him yesterday, in a meeting. I didn't know him well at all, but he was a very good professor...he was going to be on sabbatical next year. This is a complete shock...I don't know what happened, but it must have been sudden, because he seemed perfectly healthy yesterday afternoon.

My deepest condolences go to his friends and family.