Android Market In-app Billing is launching in the next week, Google announced today.
"In preparation for the launch, we're opening up Android Market for upload and end-to-end testing of your apps that use In-app Billing. You can now upload your apps to the Developer Console, create a catalog of in-app products, and set prices for them. You can then set up accounts to test in-app purchases. During these test transactions, the In-app Billing service interacts with your app exactly as it'll for actual users and live transactions," stated Google.
Note that although you can upload apps during this test development phase, you won't be able to actually publish the apps to users until the full launch of the service next week.
To get you started, "we have updated the developer documentation with information about how to set up product lists and test your in-app products. Also, it is absolutely essential that you review the security guidelines to make sure your billing implementation is secure," said Google.