From post:
Is the implication here that most wireless routers allow administration over a WAN interface by default? That's simply not true...

Response:
No, remote admin mode isn't needed since an infected router would be attacking another router by first joining that router's network (after having cracked WEP, if appicable, and then cracking the admin p/w to update the firmware on the router w/ code that self-replicates).

Not sure how feasible this is given the rather diverse array of routers out there (unlike the more monocultured Windows world). But a scary thought, nonetheless.