USGS Quake Monitoring and Reporting Site
I'm not sure how fast it is updated, but you can click on the map or listing of reported and verified quakes to see details about where they struck, how deep they were and their magnitude.
Poke around on the site to check out some of the historic data such as quakes in the US from 1750 to 1996 or the top quakes in the US or World.
