You make a good point, and I'd considered the "just because it's legal doesn't mean it’s not censorship" idea as I'd written my post.

Moore may believe that what Disney has done is censorship (as others clearly do), so I must concede that his point must be considered. However, he's using the strongest possible terms to denounce this act when he calls it un-American, and yet the idea that this is censorship is highly debatable at the least. I suppose that is Moore and the way he communicates, but I find it to be the kind of highly charged language that many people (on all sides of the political spectrum) use that really turns me off.
As far as my half-right view (and I can live with being half right in this case) of this not being censorship: there are lots of business that don't carry a product because of its content. Is it censorship that some video stores don't carry x-rated videos? Is it censorship that Christian book stores don't carry Muslim books? Or how about non-religious book stores that carry very little Christian literature? Or more to the point, I hear that Mel Gibson had several companies turn him down for "The Passion of the Christ", which I can only assume is due to the content. Clearly many people were afraid of being involved with a movie that might be branded anti-Semitic, and yet that doesn't seem to me to be censorship. I don’t even find it morally reproachful. I’m glad Gibson got his movie made, but I don’t see any reason to fault the companies who thought it too high a risk to be involved with.

It is interesting where the line is drawn between what is censorship and what is not. This discussion has caused me to think through it a bit more than I have in the past, but to me there still must be a proactive element for something to truly be censorship. If I fail to pass along information presented to me by a Muslim then I am not censoring that person (though if he has paid me to and I've accepted the task I'm certainly behaving immorally). However, if I attack that person for stating their beliefs (and by "attack" I mean in any fashion: physically, verbally, boycotting, politically, etc.) then I'm engaging in censorship.

Whether or not there is such thing as "moral" censorship or if all censorship is inherently immoral is yet another interesting discussion, but I'm too tired to engage in that one!