After a few years of rarity, unlimited data plans are a thing again. Verizon kicked off this recent round of plan changes with its unlimited plan last week. It was then followed by T-Mobile, Sprint, and now AT&T. Like Tmo and Sprint, AT&T had an unlimited plan, but it's making some changes. The main one being you can buy it now—no more restricting access to DirecTV subscribers. It's still way expensive, though.
AT&T's unlimited plan is pretty much what it sounds like. You get unlimited talk, text, and data... up to 22GB per month. After that, you might be throttled during peak usage times. You also get no tethering, which has long been the case with AT&T unlimited plans. Other carriers are at least offering 10GB of tethering. AT&T is in the process of rolling out its stupid Stream Saver video throttling service as well, but that will be optional.
The pricing is mostly the same, so opening up access to non-DTV subscribers is the main change. You'll pay $100 for a single line of unlimited and $40 for each additional. However, the carrier is now offering a discount if you have four unlimited lines for $180 per month ($40 off). It's the same at Verizon's two and four-line pricing, but one and three lines are way more. And of course, add phone payments if you're financing a device through AT&T.
To be honest, this doesn't seem like a very good deal (especially for single lines). Also note the discount is a bill credit that takes 2 cycles to start. And no tethering? Gimme a break, Ma Bell. Still, if you need to be on AT&T for some reason and need a lot of data, you can have it starting tomorrow.