I hate to arrive an old thread, but I now agree with jxself, not only for the
reasons stated above, but for an entirely new reason. The Creative Commons
Licenses are actually non-free.
Virtually every one of the licenses, including the two free ones, includes
something similar to this sentence in a clause at the end of section 4:
"...if You Reproduce, Distribute or Publicly Perform the Work either by
itself or as part of any Adaptations or Collections, You must not distort,
mutilate, modify or take other derogatory action in relation to the Work
which would be prejudicial to the Original Author's honor or reputation."
I'd say that's a restriction on usage.
