Move your mouse over the pictures. Woooo. :-)
If you choose this layout for your collection, you'll notice it may load slowly. One optimization which I don't do yet is I always scale down from the original image. If I want a 100x100 greyscale image, it's stupid to start with a 3.1 megapixel source image. If I already have the 100x100 color or 320x200 color, I should start with that.
I have FIXMEs where I need to do that, but I've been waiting until I've needed it several times, so I know how to best generalize a new API call for it.