The Neo900 isn't yet a definitive product as the company is relying upon crowd-funding to try to achieve their goals. The company thinks they will need twenty-five thousand Euros to bring the phone components to market while the phone components are then estimated to cost 500 to 700 EUR per unit. It's far from being a cheap project.
The Neo900 wants to be a Freemantle / Maemo 5 successor to the Nokia N900 but with a faster processor, more memory, and an LTE modem. The innards of the system would be based upon the GTA04 and obviously be open so that platforms like Maemo, Ubuntu, and Firefox OS (or others) could easily run on the hardware. Original GTA04 platforms like QtMoko, SHR, Debian, and Replicant would also be supported at the hardware level.
Among the features hoped for with the Neo900 are LTE, USB OTG, battery hot-swap, stereo in-line, IrDA and consumer IR, lots of supported hardware sensors, GPS and GLONASS, prototyping support, and a fully open-source software stack.
The "minimum" key features would be a Texas Instruments DM3730 CPU with OMAP3 ARM Cortex-A8 processor, 512MB or more of RAM, 1GB+ NAND flash, and 32GB+ eMMC. For costing nearly one thousand dollars per unit if the funding campaign is a success for this low-end hardware, it's borderline insanity and mostly a project for extreme free software fanatics or those who really want to tinker with an open phone hardware platform at the lowest levels.
More details on the Neo900 project can be found via Neo900.org.