I'm guessing two different gears ratios with out a derailer? Though peddling backwards for the other ratio, even if it is lower, isn't that advantageous, but who knows, maybe it'll be a new way to work out those other muscles.

Pretty cool I guess, I'm give them credit for trying something new, even if its only a gee whiz factor.

Looks kinda sketchy, the idler gear looks to be held on by zip ties or something, but I guess its only function is to take up the chain's slack and there aren't any strong forces being applied to it, so I guess it'll suffice