Yes, we had a medium sized earthquake a few hours ago. The earthquake, centered around the Alum Rock area near San Jose, measured about 5.6 on the Richter scale and was located on the Calveras fault. We were a home getting dinner ready when I felt the house shaking. Having experienced various earthquakes in the past (including the 1989 Loma Prieta quake), it was easy to recognize the shaking as an earthquake. I grabbed our kids and ran out of the house (my wife was out of town). By the time we got out, the shaking subsided, and there was no damage that I could see.
After we got back into the house, we went on the Web to check out the USGS site showing recent earthquakes. But in the minutes after the quake, there was no sign of it. Our younger daughter was quite scared by the whole incident---not so much by the quake itself, but more by my reaction to it. So we spent the time discussing why earthquakes happen (complete with web images of plate tectonics), how houses in the California are generally well constructed to withstand earthquakes, and how earthquakes have caused significant destruction in poorer countries that can't afford high-quality construction.
Some 15 minutes after the quake, we saw the following image on the USGS site, pinpointing the quake.
This quake seems to have caused little damage. But it is a good reminder to update (or create) ones earthquake preparedness plan. A key part of this plan is to have a survival kit. Such kits can be put together inexpensively, but ready-made kits are available as a convenience. Google handed out a really nice kit to all its employees.