The Wallet Android app will be able to do all sorts of fun things like match up your shopping lists with offers and coupons for participating stores. You'll also be able to sign up for retailer loyalty programs right from the app. You won't have to open the app to make purchases, but you can breathe easy about pocket-buying -- the NFC chip in the Nexus S is disabled when the screen is off.
Field testing of the service will start today in San Francisco and New York, with an official release this summer and additional markets coming online over the next few months. Come fall, the service will also feature digital receipts that transfer back to your phone, which sounds amazingly convenient. Signing up for Wallet and Offers is free to retailers, so even the smallest merchants can put loyalty programs and offers in the app. Google's also working on an API for banks and retailers to extend the service farther.
Google Offers looks like Google's answer to Groupon, with check-in offers, offers in ads, and location-based offers. So many offers! Apparently if you find an offer on the web, you'll be able to "save to Wallet" and the deal will sync across your devices. We're getting the news as it happens in our liveblog, so stay tuned for more info!