Well anytime you act against competition you do start down the anti-trust road.
If Windows can be slapped for forcing IE and WMP on users then by the same token Apple could be slapped for forcing iTunes and Safari on it's users.
My main issue with the way Apple does things is this..... who owns the phone once it is purchased? If I want to install Opera on my iPhone I should be able to, and efforts to block me from doing what I want on MY phone can't be justified.
I am not saying Apple should be forced to facilitate apps by adding them to it's app store, but when they take active steps to block companies from getting their app on MY phone, by issuing updates and patches that are meant to limit my ability to add an app of my choice then they are the very definition of anti-trust.
Imagine not being able to install Firefox on your windows machine. Imagine Windows taking steps that would make it so only software developed in VB could be installed on a windows machine. That is ridiculous and people would lose their minds over it.
What they are doing is removing competition, that is the very nature of anti-trust. It is one thing not to offer support for these things. It is another to block them.
If Apple said to me that installing one of these apps would void my support or warranty with them, then I could accept that, but when Apple says to me, I will block your efforts to installing one of these apps, then I cry FOUL.