this generation is already here in the form of the XDA (and possible others).
We need a new generation of mobile technology, that will bring the mobile phone, palmtop and PC closer together for this to present a viable threat.
propagating of its own accord through-out a network would class this as a worm. to elaborate, a piece of code that was written to propagate and not infect or in anyway "harm" the client machine would be a worm and not a virus. if this program propagated and did "damage" it would be a worm and a virus. and there are programs that are just virus. this requires logical or physical transportation of the code to be executed on a target client.
The point I wanted to emphasise that the thing would have to PROPAGATE of its own accord, and infect other machines, to be classed as a virus