The Due makes use of Amtel's SAM3U ARM-based process, which supports 32bit instructions and runs at 96Mhz. The Due will have 256KB of Flash, 50KB of SRAM, five SPI buses, two I2C interfaces, five serial ports, 16 12-bit analog inputs and more. This is much more powerful than the current Uno or Mega.
However it's not all gain — the 3.3V operating voltage and the different I/O ports are going to create some compatibility problems.
Also annouced at the same time are a new low cost board, the Leonardo and a new WiFi shield.
Perhaps Intel should start to worry about the lower end of the processor world.