Yes. Because AT&T and Apple told us there would be tethering, and when they DID come out with it, it required me to give up FOREVER my unlimited data plan. No grandfathering. I call BS on that, and decided I needed to jailbreak just to tether at a cost that was reasonable for the little I use it in the field (literally). It is the only reason I have a jailbreak.
As far as modifying my iOS, I purchased an ibook to read and can't read it now... fine. They are not instituting a measure to protect from piracy, they are instigating a reason for someone to actually strip their DRM.
I have purchased over $100 in Kindle books in the last 2 months between my wife and I, so I have no intention of pirating if I can legally purchase and use what I purchased. At the time, my purchase worked fine on iBooks, they changed the software to prevent it.
I don't expect Apple to support my device, because I jailbroke it. I expect Apple to not actively determine if my device is jailbroken, and disable the device or an application on it because it is. It is no different then them intentionally bricking a phone with an update because it has a user modification.
This is enough for me to say bye bye. I will go back to my Linux boxes and move over to android, on principle. I will think long and hard before purchasing another Mac Pro, Macbook or anything else Apple. Apple thinks themselves holier then thou, sort of reminds me of another company wanting to put anti-piracy software into the CPU's. I converted over to

machines after running pirated OSX on a PC... I would have never done so, but after trying the hackintosh version, I actually liked it and guess what? PURCHASED a Mac Pro. Since I have spent a lot of money on their hardware and software. This is BS, so Linux runs nicely, and dual booting Linux/Windows is just as much fun as OSX/Windows (windows is only for gaming and programing my m/c tuners). I am just tired of the BS plays they make.