What are the licensing restrictions on themes that do not otherwise specify a license in their code? A few of them look like they're Creative Commons, but a lot of them have no license specified. If no license is specified, do they inherit the BSD License like the rest of the CMS, or are they simply released as public domain? I think adding a license field to the theme descriptions would be very useful. I would guess that some theme developers would not want their themes used for commercial purposes or without any attribution, even though the CMS can be used in such a fashion.