The new iPad air is slightly thinner (@2mm) and considerable narrower (@16mm) than the iPad 4 however the screen size and aspect ratio has remained the same.
We expect that the Air will work in the lilitab system without modification however we cannot be certain until we get a sample unit to test fit.
The biggest unknown is the position of the rear-facing camera relative to the iPad 4, if the iPad Air's camera has moved then it will not be usable until we develop a new accessory panel that supports the new location.
iPad Air: 240x169.5x7.5mm, weighing 478g
iPad 4: 241.2x185.7x9.4mm, weighing 662g