1. A method of establishing a multimodal personality for a multimodal application, the method comprising acts of: selecting, for use by the multimodal application, a vocal demeanor from a plurality of vocal demeanors, the vocal demeanor being characterized by a first attribute; selecting, for use by the multimodal application, a visual demeanor from a plurality of visual demeanors, the visual demeanor being characterized by a second attribute, wherein: the visual demeanor is selectable separately from the vocal demeanor; the visual demeanor is selected based on analyzing one or more aspects of a user's history; and the vocal and visual demeanors are selected such that the first attribute of the vocal demeanor matches the second attribute of the visual demeanor; and incorporating, by the multimodal application, the matching vocal and visual demeanors as a multimodal personality into the multimodal application.