Is VoIP Secure?

Voice Over IP (VoIP) is a relatively new concept, but one that has exploded recently in popularity for both residential and commerical telecommunications. Home users and companies have a hard enough time keeping viruses, trojans and malicious attackers off of their networks as it is. Does VoIP provide any new vectors of attack or open up the phone system as a new target? This article from Network World by Cara Garretson addresses some of the facts and hype related to VoIP security concerns: VoIP security threats: Fact or fiction?