I'm going to come right out and say it: I hate Sudoku. Don't get me wrong, I can do Sudoku puzzles and I even know some of the tricks and (god help me) the terminology for the various combinations of empty boxes. But it's not my bag, my bag is crossword puzzles. So seeing this pop up inside installer.app is welcome.
It looks like getting the .puz files is a bit of a hassle -- it would be better to have a source list of online puz files, but these are getting tougher and tougher to find these days anyway. Otherwise, great native app. Come on, you have an iPhone, which makes you cool. Language puzzles are so much cooler than mere number and logic puzzles. If you're jailbroken, hop on over to installer.app and give it a shot.