Well, I just took down my pro facebook page after reading the fine print on the copyright info. Sorry to have steered some of you in the wrong direction. I don't feel it's safe to post art on Facebook when they state under terms and conditions:
"When you post User Content to the Site, you authorize and
direct us to make such copies thereof as we deem necessary in
order to facilitate the posting and storage of the User Content
on the Site. By posting User Content to any part of the Site, you
automatically grant, and you represent and warrant that you
have the right to grant, to the Company an irrevocable,
perpetual, non-exclusive, transferable, fully paid, worldwide
license (with the right to sublicense) to use, copy, publicly
perform, publicly display, reformat, translate, excerpt (in
whole or in part) and distribute such User Content for any
purpose on or in connection with the Site or the promotion
thereof, to prepare derivative works of, or incorporate into
other works, such User Content, and to grant and authorize
sublicenses of the foregoing."
Oh well...live and learn. And thank you Kate for your wise warning!