AT&T has declared war on net neutrality by introducing bandwidth limits on domestic customers.
I presume that the basic idea is to stop people from cutting the cord and taking their TV over broadband (just like they could take their voice over IP).
There's really only one response to this - ditch them, fast. Even though the barriers are set high, no doubt they will come down, and AT&T deserve to lose all of their customer base over this regressive move, but, unfortunately, now one of them has twitched, I suspect that other service providers will follow.