The mobile smart phone market is certainly a healthy one, and powerful devices are getting into more hands (for both consumers and businesses). There are a few great selections to choose from; RIM's BlackBerry, Microsoft's Windows 7, Google's Android OS, and Apple's iPhone. The latest incarnation of the Apple iPhone hits store shelves today, although from first glance it looks the same as the previous iPhone 4. Let's take a look at some of the differences.