Can you explain what you mean by this?  You want a way to keep people from adding new favorites?  Why?

Want to keep them from being removed using the remote.  It's for a VAR who has SBs installed in hotels/restaurants/etc, and sometimes they get deleted by accident by the end user.

A note from Jez:
on the favorite lock, I'd change it to maybe say that favorites can only be
added, changed or removed via the web interface. This might be a useful
feature for various types of 'service providers' that want to be able to
offer a managed range of content that customers can't fiddle with.
Especially if they can also hide other SN menus at sometime in the future.

OK I can see where we might want a "lock favorites" checkbox on the SN Favorites web page.  For these service providers, they should really create just 1 favorite entry that links to an OPML they have created with their directory of 'favorites'.

SN menus can be hidden using the Menus tab on Player Settings.

Will review the outstanding SN bugs after 7.0 ships.