I need to share a folder of documents with the members of a google-group. Is there an easy way to specify that (other then just listing manually the email addresses of each member of the group)? It would be nice if it will also handle dynamic changes to the list (that is, will automatically share new members added to the group). (google-docs does that, but being a user of Ubuntu One means that it would be easier for me if this functionality could be achieved with U1).
No, there is no way to do this currently.
While you can send the invitation mail to a mailing list, the invitation will be accepted by the first individual Ubuntu One account that "uses" it.
That means the rest of the mailing list users will have an invitation that doesn't work. So, you should send invitations to each individual email that you want invited.
On the other hand, a "mass invitation" tool would be a nice application of our 3rd party APIs :-D
More information about them at https://one.ubuntu.com/developer/