In-app billing is now live in the Android Market. The feature allows Android ap developers to charge within an application for additional features, upgrades or app-functionality.

The service officially went live yesterday, and at launch had several applications already taking advantage of the service including including Tap Tap Revenge by Disney Mobile; Comics by ComiXology; Gun Bros, Deer Hunter Challenge HD, and WSOP3 by Glu Mobile; and Dungeon Defenders: FW Deluxe by Trendy Entertainment.

What do you think about in-app purchasing? Do you like the idea of upgrading within an application, or would you rather purchase a whole new version of an app to get updates that cost additional cash?