Uh huh... so it can infect Linux after you click the applet to "trust" it.
This like saying giving someone a shell script to rm -fr / and having them run it is infecting the system.
The title should probably be something like "Koobface Would Infect Linux Systems Too, If It Could Be Bothered".
Well, it was the exact same situation with OS X (you had to explicitly trust the self-signed applet when asked), and that was apparently still news-worthy, so this is no different.