Nay, it's implemented as currency by NXT-NP45-W9T8-E78H-3B8L7. I can only assume it's done that way for the usability in Nxtty app or something. Like, swap a large amount of Nxttycoin to this one, perhaps.

Edit: I'd say tradable as you can use it for up/down betting, really. This is very common in regulated markets (like ETFs and stuff), so why not here? Possibly it could be turned into an asset, but the value has to come from somwhere (like users or app income or something).