As of July 1, 2009, we lost Nevada, but that still leaves 28 states in which California residents can use the Utah permit.
Please periodically visit link below for Utah BCI's page on reciprocity/recognition.
Utah Department of Public Safety.
Of the states below that have formalized reciprocity or recognition with Utah, there are some states that will only accept the Utah concealed firearm permit so long as the permit holder is a resident of Utah.