Development of Creative Commons licenses

["Greg London" <email AT greglondon.com>]

Branko Collin said:
> CC has produced a pie chart showing how CC-licenses are used on the
> web: http://creativecommons.org/weblog/entry/5293

Finally had time to take a decent look.
I'm a little concerned that the biggest slice of the pie
is an oxymoron of a license: CC-NonCommercial-ShareAlike.
A market economy license (non commercial) to gain free
advertising, free distribution, and free fan-generated
hype, but with an added restriction (share alike) that
usually is reserved for gift economy licenses, but here
only serves to further restrict the way fans can use the
work.

The second biggest slice is NonCommercial-NoDerivatives,
and I suppose CC-NC-SA is less resrictive than CC-NC-ND,
but i can't see any real world difference between CC-NC-SA
and plain CC-NC.

Does the ShareAlike addon gain anything?  Or is it the
reflection of a lack of understanding of the licenses by users?
Do people get caught up in the idea of "Sharing" their
content and so they add ShareAlike even when it doesn't
make sense when you've got NonCommercial in front of it?