I don't get why this is so newsworthy and "innovative". Matias makes a good line of keyboards[0] (even a mechanical one!) based on the same concept, just with 1 wireless and 1 wired connection. Wired is a lot less of a hassle for me anyway, and you don't even have to change the batteries.
That's the innovation part. 1 wireless + 1 wired doesn't help you much if you want to use it with multiple mobile devices (tablet + phone, for example) besides laptops.
[0]: http://matias.ca/onekeyboard/