Who is it in the end that owns the iPhone? The user who paid for it, or the company who manufactured it? That is the question that has led to a lot of bitterness between those who want to jailbreak their iPhone without feeling like a criminal, and Apple who wants to maintain control over the device after it is sold. Now Apple is set to head to court to defend their stance against jailbreaking.
Their opponents, Apple customers themselves, are wishing for the US Copyright Office to allow for an exception in the Digital Millennium Copyright Act (DMCA), so jailbreaking is no longer considered illegal. This could be troublesome for Apple, who currently acts quickly to take down sites and servers that host jailbreaking software or provide information on how to get it done. It's a common move for them, which unfortunately often puts them at odds with their own user base.
Apple isn't the only company who could be affected by this lawsuit – Google also attempts to discourage, if not outright ban, the ability to jailbreak Android on T-Mobile phones, however Apple certainly remains the most covered opponent of jailbreaking, primarily due to the sheer success of the iPhone and its App Store.