you can wait a few weeks for a due. 5x the processor speed, familiar api. or try the teensy 3.0, chipkit, pinguino, propeller or leaf labs maple. all except the propeller have arduino like ides and apis. all except the maple are available from adafruit. adafruit sells the pic32 version of the pinguino. there's also an arm version out there somewhere. and a pic18, i think.
and don't forget the mbed. also available from adafruit.
"If I had known it was harmless, I would have killed it myself." - Phillip K. Dick, A Scanner Darkly