Here is what I was able to get from one of the admins of Dreamcast-Junkyard, Segabits and other sources.

So far everyone at Sega Japan seems to be fine and no damage to the Sega Corporation. The Sonic 4 contest winners from last year are also in Japan at the Sega offices as well as the administrator of Dreamcast Junkyard. He is doing fine as I just chatted with him about an hour and a half ago (he's in Tokyo).