Apple today released the third beta of iOS 6.1 to developers. The release has a build number of 10B5117b, versus 10B5105c for the second beta of iOS 6.1 that was released on November 12.

As with previous betas, Apple mentions a number of changes from iOS 6.0.1, including several related to how developers can integrate Apple's new mapping service in their apps, as well as an improvement to how boarding passes are handled in Passbook, and a few minor changes to Safari.
Apple also released a beta of the Apple TV software, as well as Xcode 4.6 Developer Preview 3. Registered developers can download the betas via Apple's Developer page or via Software Update on iOS devices with a previous iOS 6.1 Beta already installed.
















Top Rated Comments
Yep. Even multiple logins and a file system with a documents repository.
I believe iOS does support delta updates. That is why this update is only 100MB and not 1GB.
You actually don't need the app installed for a pass to work. You can receive them via e-mail or I believe through Safari as well. An app is just ONE way to get a pass into passbook.