To answer Deb's question...this was built brute force using Photoshop using the web saved versions of the photos, by copying and adding layers for each of the 20 something photos in the year in review. I started with a canvas around 5000x5000 so I had room to move them around. I then did my best to arrange them evenly across the canvas.
KarenNfld uses a slick program to build these much more elegantly, but I am too cheap to spend the coin right now!