The code on the device will be open source. If you wrote something that made it easier to use when the internet was down (or you weren't connected at all) and sent a pull-request you'd have a good shot of it being accepted. When the backend is released as O/S too there will no doubt be some effort towards getting it running on the device itself.
Dan from Ninja here. That's what happens when you try and explain something geeky to a broad audience... but for the techies...
It's a powerful (same chip as beaglebone black) ARM computer with WiFi, BLE and ZigBee radios. Runs ubuntu. Everything open source. Almost all Node.JS.
It uses open source drivers to connect to devices and learns how they operate, building a model. If something is out of place, it notifies you and gives you context aware control. For example if nobody is at home and the heater is on, it will alert the last person to leave and give them the option to turn it off.
Key new tech is positioning with little USB powered dongles placed around your house and Leap-motion style (but simpler, no 3d hands) gestures for controlling lights, temp, etc.
Everything the NinjaBlock did, but all built-in (no more dongles for wifi etc).
Actually, Ninja Blocks' next iteration due toward the end of the year will have onboard RF433Mhz, which allows you to interface with a ton of things you might already have in your house (motion sensors, door bells, door sensors, etc). These devices are super cheap and use crazy small amounts of power.
We've tried to go to great lengths to make it possible for non-hackers to interface with us, for instance you can train the platform what devices are in your house, and then make rules that might trigger anything, such as RF devices like power sockets, Webhooks, SMS, and many more.
Right now we're focussed on getting the rest of our Kickstarter obligations out (we're currently waiting on RF433 dongle's, finally due next week), and are working hard on building a platform that other's can build apps on-top of.
Edit: Don't want to steal SmartThings' thunder here, it looks really cool and we welcome the competition. Just wanted to correct the inaccuracies of the above comment.