Hi reed. I used Photoshop, essentially. I used the crop tool, while holding down shift to keep the selection square as I expanded it. Once I had an area I liked, I cropped it and then scaled down the image size to 50x50 pixels. For the non-square avatar, I simply went for the change in image size, where 50x37 pixels kept the proportions the same as the original. I then ran the images through GraphicConverter, re-saving them, to strip out any (resource) data that is unnecessary for the web. And there you go!
Oh yes, I watched Obama's speech live last night. Very interesting.