OK, I have the zoom on the quake now-the aftershocks may be defining a 40 km-long zone. The initial depth of the quake is shallow-less than half that of Northridge. That may be how the quake can be longer in along-strike length, yet a smaller magnitude. Or, we may see the magnitude upgraded a little....Richter magnitude gets saturated somewhere around this magnitude, so they have to look at other scales like Local or Moment (ML or Mw). Or, maybe they did this already.
Chris