There is no problems from the bosses here that I know of, in fact i think that they have been quite hospitable to date with some of the content that has already been posted.
If you go back, you will find a lot of imagery and evaluations from members throughout the threads.
The issues that you would have to consider and account for would be more along the lines of copyright and ownership of material, plagiarism, and compliance of any relevant Federal and State Laws.
Google is not liable for any breeches of these acts that may be committed by members, but, it becomes liable if requested to remove any such material by the owner or authority, and fails to do so.
Google is not into the business of non-compliance.
One of the tasks of the Moderators is to be aware of any material that is inappropriate regarding these issues and take the necessary actions to avoid any offenses that may be committed by members, and to respond accordingly to requests by copyright owners and relevant authorities to do so.
If and when any situation becomes a dispute, the moderators can console with the Administrators and in turn, hand the issue on to the Google Legal Team if deemed necessary.
I hope that has answered your question,,,and a bit more.