Wasted all day playing this game. Well, I wouldnt say wasted since I enjoyed every minute of it. Very easy to learn and good use of the interface.
A couple of suggestions: The difference between the easy, medium, and hard puzzles isnt that significant. The hard puzzles, while a bit more challenging, werent really that hard to figure out once I got the hang of it. I dont know how many of each level there are, but I did find myself repeating some of the levels. If you could write a script that auto-generated puzzles, this game would have the potential of being one of the greatest puzzle games released so far on the iPod Touch. Another suggestion would be to add a function where swipping a row of cells that you had already swiped to eliminate them. As it is now, if you make a mistake, you have to double tap each cell to turn it back to a blank cell. Other than that, excellent game and I look forward to updates with new puzzles.