But buying Motorola for patent protection, co-branding tablets, selling them in a store and even the existence of the Android mobile platform are all means to an end, which isn't big bucks from the hardware business, but revenue from Google Play digital content, online services and advertising.

Google is the only player in category two that's in the position to profit from the bits without stressing about the low- or zero-margin hardware business. That's its greatest advantage. Google can grow the market with reckless abandon because every new customer brings additional revenue, but not additional costs or risks.

Amazon and Barnes & Noble? Not so much.

Everyone seems to think that Amazon will continue to succeed in the tablet market. I'm not so sure.