Here are current add-on themes for the Testimonial Rotator plugin by Hal Gatewood.
This theme showcases three testimonials across in a carousel feature. If the widget is used in the sidebar it will bump down to one nicely formatted rotator.
This theme showcases a good sized headline followed by a bar, then stars and the body content. The quoter is at the bottom making for a nice arrow down look to the whole block.
This theme focuses on the stars as the main focal point with a rather large headline (pulled from the testimonial title) with the body content below.