The Atmel ATmega328P is the heart of the Arduino Duemilanove and Uno. This is the raw IC in TQFP package. The pins have an .8mm pitch. You can see it being soldered here. This ships with the Duemilanove w/ 328 bootloader, ready to be programmed via an FTDI adapter, or ICSP. There is a proven Eagle footprint in my Eagle library on Github.
Just a reminder that this TQFP package (AU) has 2 more ADC’s than the DIP package (P), but (Arduino) A6 and A7 are only analog inputs, they cannot be used for outputs – nor do they have any pull-ups on them.