If you ever ride on one of these things and feel how they move and all, you'll DEFINITELY be able to see how it could be cool for a videogame, LOL
The faster ones where I work go about 20 mph (which is pretty fast for the inner aisles of a warehouse), and in case you haven't seen one of these before, you hold the lever with one hand and twist it to go forward or backward, and then you lean to one side, pointing it in the direction you want to go to turn... Depending on how sharp the turn, that can take some serious full-body movement, but it feels cool. =P
And yeah, these are meant more for speed than forklifts. Forklifts are just for lifting things up and down, while motorized jacks are meant to quickly load pallets onto a trailer.
Anyway, can you imagine a few pissed-off guys in a warehouse, flying around and punching at each other when they get a chance? I think it'd be fun