The 503 is an odd name.
I think it should be called the 360 with a little tiny 2 just after the 0.
But who cares. While I am not big on the touchscreen part the wlan and bluetooth seem like it would be very handy.
What I was hoping for is a 360 with a 6 inch screen but identical to the current 360. Through in wlan and bluetooth and thats a winnnner. Though I am completely happy with the current 360.