Well making it round as opposed to square. I assume it is code that chooses the image to be displayed as a square and so it could be displayed as another shape. In the testimonial widgit it is drawing from the template for the size (thank you for the code fix on that by the way. I got it to work) - so I imagine that you could have code that defined the shape of the image that is displayed.
I am unsure what you mean by Google, but maybe my above description will help more.
Thanks for the widget by the way. Really helpful and easy to use. - Carlyle