Apple's free MobileMe Gallery app was just updated, and the new version finally supports the iPad.
Other changes have been made to finally bring the app up to speed with iOS 4 and the iPhone 4 -- there's now support for fast app switching, and the app is now optimized for the Retina Display on the iPhone 4.
Previously, users needed a MobileMe subscription to view friends' galleries; now that restriction has been taken away for iPhone and iPad users. The app looks great on an iPad, and if you have any photos stored in MobileMe galleries, you'll want to get this update as soon as possible.