As noted by GreekiPhone, Apple has tonight released the next version of its iOS 5 operating system for developers. iOS 5 (Beta 2) weighs in at 740MB and carries a build number of 9A5248d.

It is so far unknown what has changed in this build.

Continually updating after the break.

[Update] – Wireless sync is now LIVE.

In iOS 5.0 beta 2, wireless syncing is now available for the Mac. It requires iTunes 10.5 beta 2 and OS X 10.6.8 or Lion. You will see an option to enable wireless syncing when you connect your device to iTunes with the USB cable. It is recommended you perform your initial sync with a cable after restoring your device.

Wireless syncing is triggered automatically when the device is connected to power and on the same network as the paired computer. Or, you can manually trigger a sync from iTunes or from Settings -> General -> iTunes Sync (same network as paired computer required). Be sure your device is plugged into a power source when performing Wireless syncs.

If you find issues with apps, media and/or photos synced to your device, you can reset then resync. From Settings -> General -> Reset, choose Erase all Content and Settings. Then reconnect to iTunes and sync again.

[Update 2] – via iFans. (they’ve got the full change-log, so be sure to head over).

Highlights include:

- iTunes 10.5b2 can’t sync iOS 5 Beta 1 devices
- iOS5 Beta 1 devices can’t iMessage iOS5 Beta 2 devices and vice-versa
- WiFi sync now works with OS X computers; it has to be enabled in iTunes 10.5 beta 2 first
- OTA updates have been released, though none are currently available
- iCloud has a new logo in the Settings.app
- You can now backup to iCloud or the computer when setting the device up
- If no notifications are available, Notification Center shows the text “No New Notifications”
- Stock widget in the Notification Center is now off by default
- Stock wallpapers are back, but are the same that were in iOS 4
- General speed improvements, kills bugs that were present in iOS 5 beta 1