The only option in my Shared Photo Stream appears to be "Edit", which lets me add/delete photos. Can I rename the title perhaps online somewhere?
Go back one screen to the main Photo Stream screen. From there, tap on the blue arrow for the Shared Photo Stream you want to change, and you can edit the name, subscribers, etc.
Main screen showing the blue arrow on the right:
Sub-screen after tapping on the Photo Stream I want to modify:
New method for iOS 7, 8, and 9:
- Open the Photos app
- Make sure you're on the iCloud Photo Sharing screen (tap back as necessary)
- Hit Edit (top right)
- Tap on album name text from listing
- Make your edits
- Tap Done to save