Idea, solution, functionality, design etc are exactly what most would like to have. I hope 720p is just a beginning and in near future we will see similar solution at least 1080p each channel with descent bit-rate and IQ.
Things are slowly inching in the right direction but i would still like to see SD cards get dropped from larger setups, in favor of USB thumb drives or SSD.
It is counter productive to have a hidden main unit you have to get a hold of ever so often to recover footage on Sd card, so i assume it will not be that hidden in many setups.
I still prefer a SSD in a truely hidden box, and then a USB wire comming off that with a female A plug in the end where you can plug in a thumb drive to recover footage on.
Either dumping footage to USB drive on detection of that, or you can pick and choose on your app on the phone ( wifi / bluetooth ) witch footage to recover to USB drive.
I know you could dump footage via WIFI to phone or tablet, but i am not crazy about that route.
One upon a time there were USB transfer cables and also thumb drives equipped with a small button on the wire to launch a tranfer/backup of a specified folder ;-)
With it you could really let the central unit (PCB & ssd) hidden under the dashboard !
Of course dc control (and transfer) through WiFi will also work...