As you may know FTDIChip makes more than USB to TTL chips. They actually manufacture pretty advanced microcontrollers that are equipped with dual channel USB Host/Device controller. Microcontrollers with code name Vinculum-II (VNC2) have all features you may find in almost any modern microcontroller – these include 16-bit MCU core, 256KB Flash and 16KB SRAM. There are also USAR, SPI, PWM. But of course their strong side – two channels USB that can run as host or device.
They decided to make life easier for prototypers by putting MCU in a Arduino like development board. Pin-outs seems to be same as Arduino with 10 more digital I/Os. Hopefully platform is compatible with Arduino shields. FTDI also provides free software that enables compiling C programs. So new Arduino like player with advanced features.