Google announced the sunset of Google Checkout just last night, which came as a complete surprise to pretty much everyone outside of Google, including us:
Google has posted further details here:
Although Google Wallet will continue in some form, it appears that will no longer be suitable as a general-purpose payment method for Web-based purchases -- i.e., Google Checkout was the service that allowed online merchants to accept Google Wallet payments from buyers on their Web sites, and so once Google Checkout is discontinued on November 20th, 2013, buyers will no longer be able to use their Google Wallet to pay for purchases from a Web site after that date.
Of the three alternative services Google is recommending for migration, only Braintree is an actual payment processor (Shopify is a hosted storefront similar to Etsy, and FreshBooks supports email invoicing to request a payment), so we'll certainly be looking into Braintree as a potential new payment processor we could support.
We may also be considering Amazon Payments, Stripe, Dwolla, among others. We'd be glad to accept suggestions of other payment processors our sellers may wish to use, especially ones that support international merchants based in a broad range of countries outside the US and UK.
Regarding Bitcoin in particular, please see my related reply here: