While not specifically called out as part of Apple's iOS 5 "cutting the (iTunes) cord" initiative, the ability to finally create and manage photo albums directly on-device for iPhone, iPad, and iPod touch is part of just that. No longer are you stuck with what you sync over via USB. Now you can add a new album and move photos between albums and from Camera Roll and Photo Stream (for iCloud) to albums.
Only Photo Stream pictures appear to be
synced stored and pushed to all your devices, however, not the folder structure. That's a little disappointing. It would be great if whatever folder system you set up on your iPhone -- family, friends, dogs, hawaii trip, etc. -- would automagically be replicated on your iPad or iPod touch, but... baby steps.
Along with the photo editing features, on device album management is a great addition to iOS.