One Cell Phone. 2011 will bring us connectivity and authentication like we've never seen before. Our devices are ours and we use them constantly. The cell phone will be used for transaction and identification purposes. Stores, agencies, organizations, schools, everyone will start to use your phone to identify you. It will also be used to pay for food, purchases, anything. ...Not only pay but receive payment as well!
Ok, so the username and password won't completely fade... you will have to use them to log on to your devices for the first time. Once logged in your profile will always be there. Fingerprint readers will be integrated in the phones for security. That should soothe the worried mind.
If a device is lost, use one of your many other devices to track and locate your lost device. If your device is stolen you---or it-- will report it missing and it's location. The cops will be able to verify the information and get your phone back.
What is the downside of not having to remember any usernames, passwords, where your wallet is, or where your keys are? I'm sure the antagonists and pessimists will think of some.. but I am excited for the comfort, ease, and security that will come from having all these important things on one traceable device.

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