Uh, don't take me as a fanboi, I wouldn't be caught dead owning an Apple product.
But I don't believe that Apple's policies constitute violations of anti-trust laws, because, as I said, there is a viable competition. Consumers have the very real and reasonable option of telling Apple "go forth and multiply".
What I'd concede, however, is that jailbreaking is technically a crime (violation of DMCA). That twists the concept of ownership.
So, if I were a US citizen, I'd be demanding the government to fix the intellectual property rights regime for good, instead of interfering in a single firm's policies. The disease is more deep-rooted. Focusing on symptoms won't do much good in the long run.