I just left the followiing comment on a Creatice Commons blog thread debating the NonCommercial and NoDerivatives options:
I speak as founder and President Emeritus of the Open Source Initiative. The NC option in Creative Commons has always been a bad idea and should be removed.
The reasons it should be removed have nothing to do with any of the deep philosophico/political positions usually argued in the debate, and everything to do with the fact that there is no bright-line legal test for “commercial activity”. This ill-definedness is reflected in community debates about whether commercial means “cash transactions” or “for profit”, and it is the exact reason the Open Source Definition forbids open-source software licenses from having such restrictions.
The founding board of OSI, after studying the possibility, judged that an “NC” option in open-source licensing would create too much confusion about rights and restrictions, too many chilling effects on behaviors we did not want to discourage, and too many openings for vexatious litigation. What is only a source of contention within our community could prove very damaging to it if unsympathetic courts were to make even mildly adverse rulings.
I have seem no reason to change that judgment, and I think it applies with equal force to Creative Commons. The NC option is a dangerous trap and should be removed.