This is a test of thumbnail sizes, one floated right with a 10 px horizontal space and linked to the full sized file. The other is floated left with 10px vert and horiz spaces. Both are sized to 150X120px. This test was conducted using the new file upload features inthe WP 2.1 version. The thumbnail autogeneration does not allow custom sizing. When you try to make the thumbnail larger its quality goes down.