Development of Creative Commons licenses

[Sigmascape1 AT cs.com]

Hi,

Just out of curiousity, is the Attribution ShareAlike license kind of thought 
of as the "GNU GPL of creative content"? In other words, you can copy it, 
distribute all for free, but if you enhance/change/build upon it, you must, 
in effect, return it to the community?

I am playing around with some licensing options, and have not used the 
Attribution ShareAlike license before. I see some potential with it for some 
of my works.

Thanks!!

MLF

www.sigmascape.com