1. An image sensing system for a vehicle, said image sensing system comprising: an imaging sensor comprising a two-dimensional array of light sensing photosensor elements formed on a semiconductor substrate; wherein said imaging sensor is disposed at an interior portion of the vehicle proximate the windshield of the vehicle and wherein said interior portion is at or proximate to an interior rearview mirror assembly of the vehicle and wherein said imaging sensor has a forward field of view to the exterior of the vehicle through the windshield; a logic and control circuit comprising an image processor for processing image data derived from said imaging sensor; wherein said image sensing system identifies objects of interest by processing said image data to identify objects of interest based at least on spectral differentiation; and wherein identification of objects of interest is enhanced by comparing over successive frames image data associated with objects in said forward field of view of said image sensor.