We have covered all the iOS 5 announcements in the past few days in our roundups and daily coverage, but there are so many new things about the new OS for iPhone and iPad that it would be impossible to list them all in a single article. So we have collected 10 videos from YouTube that show some of the most interesting aspects of iOS 5, such as Notification Center or the new custom vibration alerts for your Address Book contacts.

Check out the video gallery after the break.

A quick video tour of the new features in iOS 5.

Notification Center on the iPad 2.

Photo Stream, the new iCloud service to share your most recent photos across all your devices.

iMessage, Apple’s new messaging solution to text iOS users for free.

Apple’s new “PC-Free” setup, which doesn’t involve a computer to activate and start using a new iOS device.

Twitter integration in iOS 5, one of the biggest new functionalities that allows you to tweet photos and URLs without a third-party app.

Custom Vibrations, a new feature from the Accessibility settings.

LED flash alerts for the iPhone 4.

AirPlay mirroring, a new functionality to wirelessly stream your device’s screen to an Apple TV. Firemint has already announced that Real Racing 2 HD will support this with an future update.

iPhone 3GS Vs. iPhone 4 comparison video, confirming that most of iOS 5 features work just fine on the older iPhone models.