I was also wondering how many of the nay-sayers here might be travel agents.
I have to say travel agents could represent themselves in a far better light by just saying "we don't like the fact that Carnival cut our commissions" than it does to criticize them just to hurt their business.
Trust in the advice in a travel agent is an agent's most important asset. If a travel agent is insulting Carnival publicly (without disclosing the real reason he is upset), or steering clients who want Carnival away from the line, I would be very disappointed in the way that person represents his profession. That is just plain street fighting tactics that hurts the client as much as it hurts the travel agent.
I know our resident agent here at CM, Pete Peterson, has been very forthright in telling us the truth about changes in Carnival's commission policy, which is an aid to cruisers going to agents who may not understand why there is a sudden "dislike" for what agents used to consider a popular cruise line.