I guess a M9, probably in the next 600 years. It has been what, 307 years since the last one. I guess for M9 it would take the whole subduction zone from Mendocino to Canada (?). I imagine it must go as M8s some of the time...not all in one piece. I don't know the area, but I think south of Mendocino you have the right-lateral San Andreas system and there should be not only the San Andreas, but associated faults, not all of them known. I saw a poster a year or 2 ago (Lippincott et al., a distant relative) where that group had discovered an active fault at the coast. You might as well sleep at night, but you could suggest that they not have heavy objects that could fall on the precious granchild's bed. I suspect the site conditions for shaking might not be so bad: not as intense as LA or Ventura basin....
Again, I don't work up there and don't know the area.
At Antarctic meeting. Talked to a professor who was a grad student with me who was caught in a storm that blew their snowmobiles in the air and destroyed all their tents but one. Guess they must have been soiling their shorts round about then.
Chris