When is a farm a farm? When is rural rural? Has the issue of the rural-urban continuum returned? Decades ago rural sociology worked itself into two blind alleys: rural-urban differences and attempts to define the rural-urban fringe. Although these conceptual problems eventually were exhausted, recent developments in California raise the possibility of a phoenix-like revival, although in new form. Three cases--the success of Napa Valley winemaking and the urban crowding that has accompanied it, the explosion of wine grape acreage in neighboring Sonoma County as demand for premium wine grapes has increased dramatically, and an antibody-manufacturing goat "farm" in Santa Cruz County--have spurred community controversies and are now generating debates over the definition of "agriculture," whether agriculture is rural, and "When is rural rural?" (Contains 17 footnotes.)