Comment by userbinator

I feel like injecting headers is only the start of something far more pernicious; even SSL/TLS can't stop an ISP from determining and tagging where your traffic goes (and consequently, passing that information onto third parties) - all your traffic goes through equipment on their network, after all. As long as your connection to the Internet is tied to your identity in some way (and there is basically no way a non-free ISP is going to let that be anonymous), they can track you. "Obfuscatory routing systems" like Tor can help, but as long as ISPs can observe the traffic on their networks, they know.