Good distinctions, but a point of clarification.
Worms are self contained and target Systems (OSs, embedded devices of particular make, etc). They contain all the code necessary to spread from system to system using whatever media they are designed for.
Viruses target applications with communciations capabilities. A spam virus for instance generally targets an email client for instance. the virus requires the vulnerable application to transmit itself from vulnerable system to vulnerable system however; that code is not contained in the virus. Viruses do not require human interaction as a rule (some do, some don't). Automatic application updates and hardened code on the few types of applications capable of supporting a virus, have largely made them extinct.
Trojans DO require human intervention, but are the most flexible. Worms and Viruses are peer-to-peer only, whereas Trojans are client-server. For instance Drive By Download attacks from malicious web sites are now the infection-vector of choice these days, because it requires as little human interaction as possible.
The malware described here, would be a worm, because it is spreading of its own accord, and does not target a specific communications application.