Irish blogger and Microsoft MVP Aidan Finn has collected a list of "designed-for-Windows 8 devices that will be available at or soon after Windows 8 general availability (GA)." The list is in an Excel .xlsx file downloadable from the blog page.

Finn's list is useful, but has no official status. As he notes: "You'd be amazed how inconsistent some of this information is, e.g. no one can agree on the name of the new Toshiba 'slider.'"
He helpfully includes not just names, but also resolution, the CPU, mass storage, RAM, battery life, weight, and thickness where available, as well as which are running Windows RT as opposed to full Windows 8.