This is a lovely piece of software, and something I've been looking for (on and off) for at least a year now. I do have one request I'd like to add to it, however.
I'd like to see an option to sort out just one specific resolution, or a list of specified resolutions, so that I can run the program on my bulk image downloads folder and pull out all the images that are wallpaper sized, without worrying about having hundreds of extraneous folders created that then get in the way of other sorting (exactly 400 folders created this batch, amusingly).
As an added bonus, but much lower priority, a sub-option that would create a second folder for images that almost match the required res but not quite, e.g. 1682x1050 or 1680x1040. Perhaps with a definable pixel or percent range.