I'm not sure externals are dead - they've just morphed into something better. I've got a buddy who absolutely loves his Osprey Atmos 50, and I've used the same pack with success. (However, my own preference is toward internal frames with backpads, since I use them as an extender with my short sleeping pad.)
It's a newer, better version of the old e-frames: advances in material and design mean you don't need the half-inch "pipes" that made up the old frames - the Atmos frame is a lot more like arrow shafts (same improvement as tent poles: no more Eureka Timberline tubes, but the slimmer and stronger pole sets we all know and love.) However, the general structure of the Atmos remains true to the classic design: a visible perimeter frame, with a few bends, and a couple of arched cross-members behind a tightly-tensioned trampoline mesh back band. As a result, you get the same great ventilation as the old Kelty, Jansport, and Camp Trails packs we grew up with.
There's nothing old-school about the pack bag, though: it has a hydration pocket (and an option to use the space between the frame and trampoline for the hydration pack, when space inside the pack is at a premium.) The packs are as streamlined as the modern internal frame bags, and retain one feature of the old Dana Designs Terraplane we all lusted after: long, vertical "sausage" pockets on the outside.
As a result, this hybrid eliminates most (but not quite all) of the one annoying feature of the old externals: the tendency of the frame to move against you as you turned, instead of moving with you.
Maybe other designers will start updating the old external styles, too.