ARM Cortex-M4 processor which has the highest performance in the Cortex-M family and includes control and signal processing capabilities. For pricing and availability see this Atmel press release.
The SAM4L-EK evaluation kit features an ATSAM4LC4C with 256K flash and 48MHz max clock frequency. The kit includes an on-board Segger J-Link, capacative touch area, USB device connector, light sensor, audio jack, segmented LCD, a wireless interface header and an add-on board header for Atmel Sensors Xplained boards. A unique feature of this board is the real-time power monitoring section with OLED color display.