Microsoft announced some major changes for SkyDrive today, including a new version of the iOS app that enables photo backup to the service and improved Facebook photo sharing from the web experience.

That first one is a big deal: One of the big advantages of using a Windows Phone is that all of your photos and videos can be automatically backed up to SkyDrive. Well now this is a feature of iOS too, courtesy of the new SkyDrive app for iPhone, iPad and iPod touch.

Here's what's new in the new version of SkyDrive for iOS.

Camera Backup. You're prompted to enable photo backup when you first run the app and, as with Windows Phone, you can configure it to back up the original photos or smaller, resized versions. There's no option for videos, but it appears that if you enable this feature it will backup both photos and videos.

Improved Office Mobile integration. With this version, the SkyDrive app offers improved integration with Office Mobile (iPhone/iPod touch only) and OneNote Mobile, so you can do things like edit Office documents with the native apps instead of using the old Quicklook viewer. (I'm actually surprised that's a new feature, but whatever.)

iOS 7 look and feel. No surprise here, but the SkyDrive app now picks up the elegant flat look of other new iOS 7 apps.

More. SkyDrive for iOS also features various unnamed bug fixes and performance improvements.

You can download SkyDrive for iOS from iTunes. Or, check out this video for more information:

In addition to this new SkyDrive app for iOS, Microsoft also announced some changes to the SkyDrive.com web experience that make sharing photos via Facebook easier. Now, a Publish To wizard will step you through the process and let you do things like set permissions.

Looking good.