Underway
Here are scenarios that are currently underway, with links and resources. A quick perusal of this list shows that there can be many different types of scenarios, with different purposes, levels of detail, and audiences.
Hayward Fault (East Bay, CA)
Work on this scenario is beginning, under the direction of the Northern California chapter of EERI.
New Madrid Earthquake Scenario
The New Madrid Chapter of EERI is developing the New Madrid Earthquake Scenario (NMES) with the aid of the Central United States Earthquake Consortium (CUSEC), the U.S. Geological Survey (USGS) and many other professional organizations.
Wasatch Front, Utah
A number of studies have been conducted recently to help understand the earthquake problem in Utah, particularly the problem with unreinforced masonry construction.