Google has announced that Google Checkout will be retired effective Nov. 20th, 2013, so your E-junkie checkout and Buy Now buttons for Google Checkout will continue working to accept Google Wallet payments from buyers until then, and the button images right now already show the Google Wallet logo.
After Nov. 20th, Google Checkout will apparently continue in limited form, rebranded as "Google Wallet for Digital Goods", so this checkout method will no longer work for selling tangible goods that require a shipping address or shipping charges after that date; otherwise, from what we've been able to tell at this early stage, our existing Google Checkout integration should continue working as-is with Google Wallet for Digital Goods beyond November. By that time, we will have means in place to detect when an order contains tangible goods, so we can disable the Google Checkout/Wallet checkout button in the buyer's cart in that case.
We are also evaluating other, more full-featured payment processors that we could start supporting as an alternative to Google Checkout/Wallet before November. Meanwhile, this help page lists the payment services we currently support: