TSA told us this back in 2010.
On a recent trip, I had my ultrabook, a Windows 8 slate, and an iPad mini. In the future, I'd like to leave the ultrabook at home and travel with a Win8 slate and a detachable keyboard.
Eventually, the TSA may change their policies, but I hope that doesn't happen anytime soon.
Win 8 tablets are fully functional Windows PCs that can run enterprise-level applications. Don't get these confused with Windows RT tablets.