In-Stat, a technology market research firm, says almost 8% of U.S. households are using Voice Over IP (VoIP). Leading the pack in VoIP services is Skype with 2.1 million households, followed closely by Vonage and Time Warner Cable with 1.7 and 1.6 million respectively.
According to a survey of thousands of households by In-Stat, 7.9% of U.S. households used some type of VoIP service. 12% of those households used a completely software-based VoIP client like Skype or Yahoo! Messenger. 49% of those with VoIP discontinued their regular phone service.