Tablet computers are all the rage right now and everyone wants in on the action. Although it might feel like there are endless options for the consumer, most of the devices are more similar than they are different, especially in terms of software. While iOS is limited to Apple's products, Google's Android can be found on just about all other mobile devices -- tablets or smartphones.Although you may not realize it, there exists a third competitor in the tablet OS market: Microsoft. Over half a dozen manufacturers offer Windows 7 tablets, including the ViewSonic ViewPad 10Pro, Acer Iconia Tab W500, Fujitsu Stylisitic Q550, HP Slate 500, EXOPC Slate, Asus Eee Slate EP121, Motion Computing CL900 and of course, the MSI WindPad 110W. With so many Windows slates in production, why don't you hear about them more?