Let me guess ... Japanese & Europeans already have this on their phones, and phones in the US won't be able to work with this for another 3 years while the "network is upgraded" or somesuch.

Seems like a brilliant, and disruptive, idea, but also like one whose time hasn't quite come yet.

There are some enterprises cooking similar products for that future market,
[textually.org...]

There are also external "nano" projectors, so you can choose the source between your phone and PDA, a maybe more flexible solution:
[slashphone.com...]