Of all the mass-murderers about the place, I personally find Rousseau the most appealing, but to each his own...
At any rate, I shall be most annoyed if she has died, as she will presumably take several secrets to her grave. The nature of her science team mission, the nature of the "sickness", and whatever insight led her to describe the "Cerberus" entity as a "security system" (which, let's face it, is the single most informative statement we have had on the wretched thing since "Pilot Pt. 1"). Or perhaps, via her death, the writers hope to get out of answering these issues, along with various others that stand little chance of ever being resolved (How long, for example, since anyone mentioned the Numbers?).