I notice a lot of newbies are getting this error (myself included):
avrdude: stk500_getsync(): not in sync: resp=0x20
avrdude: stk500_disable(): protocol error, expect=0x14, resp=0x20
While the FAQ mentions many possible problems & solutions, it seems to leave out a pretty common one, that's only cropped up with the introduction of the 328.
People keep choosing (or it might be the default):
"Arduino Diecimila or Duemilanove w/ ATmega168"
Changing it to
"Arduino Duemilanove w ATmega328"
solves the problem.
While there is a line about choosing the correct board in the getting started tutorial, I and many others seem to miss it. So how about putting it in the troubleshooting FAQ?
Later...