Wow that's great job! Thanks for sharing! I wish I found this picture yesterday when I was trying to figure out why my clock and wave shield didn't work when I moved it from Unto to 2560 
It safe me hours! I'm going to print it out and keep at my desk.
That's interesting that there are 2 more I2C connections (unlabeled on the board) above AREF, I thought they weren't connected anywhere. I wonder if one above IOREF does something too?