Via joystiq: "Games must use Sprint's SDK to take advantage of both of the screens offered by the Echo. But, how many developers will flock to create games for a single device available on a single carrier? We're going to guess: not many."
DOA. Ok maybe not DOA, but I definitely don't see this phone selling well and there won't be many apps taking advantage of the dual screens.
And in regards to the battery, "Removable 1370mAh battery; includes spare battery (1370 mAh) with portable charger that can also tether to the phone as an external power supply." Considering it includes a spare battery and this "portable charger"...to anyone who buys this thing: have fun making this phone last an entire day!