It would seem that Creative Cow has decided to ban users that mention competing sites. Now, moderating posts is one thing. None of us wants to go to XYZ site to read about digital production techniques and read about Viagra.
However, the wholesale banning of users (2500 at current count) for mentioning competing sites is, IMHO, beneath contempt. To add insult to injury, the site apparently brings up a misleading error message to those banned users who attempt to post on the forums.
To be honest, I never used the forums except in about 2 instances of desperation. I always hated their forum software (vBulletin / PhPBB are MUCH better solutions). So for me, the impact is of no consequence. However, our collective communities need to foster the free exchange of information in order to carry forward the flag of democratization in this industry.
Jonas over at General Specialist has more details. I am not the type to call for a boycott or anything of that nature. You should use your own good judgment. CC is a business for profit. That's understood. But, I think that they have the potential to chase away customers with this practice.