via Apple MobileMe News on 12/16/09
With Mobile iDisk 1.1 for iPhone, you can now copy and paste images in your iDisk to another application — Mail for instance — or save them to your camera roll. Simply view the image from your MobileMe iDisk, tap and hold it, and then select Save Image to save to your camera roll, or Copy so you can paste it later into another application. The update also adds email address auto-complete to make sharing files easier than ever. When sharing a file, just begin typing your recipient's name and it will be automatically completed if the name is in your Contacts list. To see other improvements in iDisk 1.1, visit the App Store.
If you already have the MobileMe iDisk app on your iPhone or iPod Touch, just tap App Store on your device, and then Updates to get the latest version. If you don't have it, tap Search and look for "iDisk" and then install it.
