Search iPad keyboard cover to get a better idea of what I'm talking about. I don't own one myself and haven't done any research to determine if there are any that are similar to the approach used by Microsoft, but there are several that are nowhere near as bulky as that one in your example image.
Microsoft has certainly taken their own unique approach to the tablet, both in terms of hardware and software, but I'd hardly call it innovation in the sense that it's something groundbreaking or monumental.
Microsoft has certainly taken their own unique approach to the tablet, both in terms of hardware and software, but I'd hardly call it innovation in the sense that it's something groundbreaking or monumental.