I'm pondering a new photography workflow where, instead of working with the JPG's directly out of the camera, that I instead convert them to PNG first.  The reasoning is that JPG is a lossy image format meaning every time you edit a JPG it loses a bit of precision, whereas PNG is a lossless image format and you don't lose precision.  That idea might not be the best, I haven't checked how well Picasa works with PNG's, in any case it let me play with what kind of image manipulation we can do in Node.js.