From email:
"...As we continue to build the Wallet platform, we must focus our priorities. That is why we are announcing today that we will retire Google Checkout..
"Merchants can continue to accept payments using Google Checkout until November 20, 2013.
"We have partnered with a few best-in-class companies to provide you with discounted migration options, so you can continue to run your business with as little disruption as possible. "