Not dumb question....but I'm curious to know too. What if we reworded it to say not neccesarily 5+ but strong enough that if you were sitting at home watching tv on the first floor you would notice the room rolling? Would this be as far south as San Francisco? Even LA? As far east as Montana?

Also Science channel just did a great documentary on Cascadia Subduction zone. I guess they know for a fact the last great quake was on January 28 (or 26th can't remember) year 1700. They have further found that quake intervals on this plate are between 300 years and 1000 years....i.e. history shows some quakes have been 300 years apart, others 1000 years. So...as we know we are at the 300 year mark now, so it could happen tonight, or, it won't happen in our lifetimes and not for another 300-500 years. Its tough to know.