Splitboards typically refer to boards that are split down the length of the board, turning into two skis for ascending mountains. Dual Snowboards has what you could call a downhill splitboard. The board is split into two across the width, giving you two separate snow skates of sorts.
Why would you want two separate boards? Quite frankly, I have no idea. These things look like a twisted ankle or ball-numbing split waiting to happen. I'd think they'd also sink like rocks in powder. In fact, they seem to eliminate pretty much every positive aspect of riding a board on snow.
According to Dual, they do deliver a new level of freedom - like the freedom to rip your testicles out of the sack. They are cheaper ($265/pair) than most boards, so there's that. Check it out for yourself to see if you can get a whiff of what Dual's got baking in the oven: