new zealand is built on a fault line, they get 14,000 quakes a year, this one was out of the ordinary but still just more of the same, relatively speaking
japan is also on a fault line, and has been long overdue (like, 50 years apparently) for a major quake
that one in china wasn't even that intense...
besides, most of the (major) ones recently seem to be along the same fault lines (give or take), so it's probably just slightly abnormal shifts in the tectonic plates
besides again, we're still a year and a half out from the supposed 2012 end date... if this is what it's like now, the end of the world isn't exactly going to be sudden...