Google Wallet got off to a rough start. Carriers didn't want to support it for various reasons, it only worked on certain devices ... it was really just a big mess. As time passed, it didn't get much better, either. Today, however, Google is looking to change everything when it comes to Wallet. It's rolling out v2.0 of the app that brings a slew of new features, as well as making it available for basically all Android phones running Gingerbread (2.3) and higher.
With the new app, you'll be able to send money to other Wallet users in the US, a feature which is free to use with a bank account. However, there are small fees associated with sending money using credit or debit cards.
Past that, you'll now be able to store all your loyalty cards within Wallet – simply scan the barcode and type the number, and you're done. Now you'll have all the cards you'll need when you need them. The updated app will also show you local offers, as well as track all of your purchase activities in one place when you pay by using the app.
The app update will be rolling out through the Play Store "this week" in the US.
The status of NFC payments has not changed. You still need a supported phone to use NFC payments even with the new Wallet app. The primary different (aside from the new features) is that it's now available on all 2.3+ phones. With that said, support for the phones doesn't equate to support for NFC payments.
Update x2: It turns out that not only is the apk rollout staged through Google Play, but activation is also staged on the server side. As a result, some users who download the app and sideload it will get an error until the rollout is at 100%. This won't affect all users, so just be aware that this issue could arise and the app will work as it should once the rollout has been completed. The server side rollout is finished, so the app should work for everyone now.
Update: Here's the APK for those who don't want to wait (read: everyone). Enjoy! Thanks, Scott!