Burley Duet [of some unknown year]; And always one less than I think I really need.
Supposedly the wheel/frame interface is stiffer with the through-axle design. Eliminates the worry of pulling a QR out of the dropouts on disc applications. Chainline is essentially a 135mm spacing. Soon, if not already, there will be far more hub options, and a LBS may be more likely to carry a 142x12 than a 145/160mm tandem hub or wheel. PowerTap even now offers a 142x12 hub for those who want. And it's different, and whether it works or not, different is cool.
I have heard that the 142 thru makes it much stiffer. I have one on a mnt bike and it seams much stiff however I really cant compare because the frame and parts are different as well. Most 142 wheels are 135 base with spacers or different axles so the wheel is not stronger. In the future the hubs are suppose to be wider creating a stronger wheel. Different is neat