In fact, AT&T announced two upcoming USB broadband modems – the Shockwave and Adrenaline. First and foremost, the Shockwave is the cheaper of the two at the nice price point of free with a contract, but you still get a device that has support for HSPA+ once it goes live some time down the road. Plus, it'll be more than equipped in dealing with their current HSPA 7.2 3G network.
On the other hand, you've got the $49.99 Adrenaline which packs a microSD slot, GPS receiver, and the notion that it'll be ready for AT&T's LTE network. So if you're ready to experience AT&T's next generation data network, these two USB modems will surely be there at your disposal.