No, they can only be edited by the owners.
There's a feature request somewhere to allow group editing, but I'm not sure that's a good idea to implement in general - as an end user, I don't want other people editing the stuff I've set up for myself.
Admins can change the ownership though, which does help a bit.
You must be a registered user to add a comment. If you've already registered, sign in. Otherwise, register and sign in.