updated 02:25 pm EDT, Mon July 21, 2014
OS X gets iTunes 12, iOS 8 gets new Tips app
(Updated with other beta releases, more Yosemite changes) Apple is now seeding its fourth betas of iOS 8 and OS X Yosemite to developers. Perhaps the most significant change is in the latter, which includes the first beta of iTunes 12. The updated media player uses a flatter, streamlined design more in keeping with Yosemite, and is the first version to support Family Sharing, something also present in iOS 8. While Yosemite is still only accessible to developers, sources claim that the first public beta could go live later this month, after Apple has put more polish on it.
The new iOS 8 beta meanwhile incorporates a Tips app. On a weekly basis the app will provide hints for using the OS, for instance explaining notification actions or turning on Siri's hands-free mode. Other changes include revised graphics for the Control Center, and dedicated Settings sections for Display & Brightness and -- under Privacy -- Home Data (associated with HomeKit). In previous betas, display/brightness settings were found in the same section as Wallpaper.
A Bug Reporter app has been removed, and Messages' Settings functions now include separate expiration controls for audio and video. The venerable Calculator app has been redesigned to match Yosemite's style, and Dark Mode has received some further tweaking, including modified "dark" versions of some menubar icons. More beta changes will likely be discovered in the next few days.
Update: Apple has also pushed out new betas of Xcode 6, Configurator, and the Apple TV firmware. The Apple TV OS is based on iOS.