Well, I've been busy on the SudokuHelper
It shows a pretty green tick when you complete a puzzle now :-)
But the cool thing is that it now shows a random puzzle on the right so when you complete a puzzle, or get too stuck you can try another.
I've also been paving the way to automatically rate puzzles on difficulty. Just added code that keeps track of how many steps a person takes to complete a puzzle which then gets stored. Once I get enough data I can then add details about the average difficulty to the puzzle.