Parkfield averaged a mag 6.0 quake every 22 years on a very regular schedule for a VERY long period of time.
So the area was wired up with more seismic monitoring equipment than any other place on earth....and then they didn't get the 22 year quake :-)
Actually pretty cool (presuming this did very limited damage, which it likely did) that it finally happened, as with more monitoring there than anywhere else on the planet, we'll learn an awful lot scientifically from this quake.
I guess everyone else in the office felt it. I was too busy concentrating on my work.
I'm up in San Mateo, about 20 miles south of San Fran, so quite a distance away.
You are correct. The "expected" earthquake was in 1988. But in that 22 year "cycle" there was one that was about 10 years "late." Some say that the Coalinga earthquake changed the stress field enough to delay the "expected" Parkfield earthquake (until today).