CALLING for “new towns” has long been a favorite activity of architects and architectural critics, but in recent years just about everyone seems to have taken up the cry. The list of such advocates now includes giant corporations, real estate developers, the American Institute of Planners, the mass media, the former President, the Urban Affairs Council of the current President, several state legislatures, various cabinet members, congressmen, senators, governors, the National Association of Counties, the National League of Cities, the United States Conference of Mayors, and Urban America.