The growing voice-over-IP industry has quietly crossed a key threshold. According to a Harris Interactive survey and a Keynote Systems' competitive intelligence study, VoIP quality has dramatically improved to the point that it outranks landline phones both in customer satisfaction ratings and in overall audio quality.

The quality issue seems to strain credulity, but it comes from a company--Keynote--that has been quick to criticize VoIP quality in the past, and is still critical of its audio delay characteristics. The company's survey covered 12 major VoIP players--AT&T, Comcast, Lingo, Packet8, Skype, SunRocket, TimeWarner Cable, TrueVoice, Verizon, Vonage, Vonics and Windows Live Messenger--that span the industry in terms of how VoIP is deployed and used. Keynote spent a month testing the performance of the various types of VoIP players against each other and against PSTN service and then ranked them using its own test and measurement products.

What Keynote found was that Comcast and Time Warner Cable outranked the rest in terms of audio quality and helped bring the entire category's overall score up to above a 4.0 Mean Opinion Score--considered toll-grade quality. But the company found that even other VoIP performers were edging up in quality, getting scores comparable to GSM phones for quality.

The Harris Interactive Survey, conducted for Level 3 as part of its ongoing series of consumer research on VoIP, showed two-thirds of those surveyed are aware of VoIP, and more than half are familiar with the service. Among consumers subscribing to the service, 86% said they were very satisfied, compared to 74% satisfaction among traditional landline customers and 66% satisfaction among wireless customers.

Also significant was the fact that 76% of VoIP users wouldn't switch back to the landline service.

Cable companies are likely responsible for a large chunk of the good feeling consumers have about VoIP. They continue to sell the service as part of a bundle and offer the installation and support that average consumers need.

Having moved away from geekspeak into the general lexicon, however, VoIP must still live up to its greater promise, which is to do much more than send phone calls over IP lines. Once quality and customer satisfaction issues are addressed, the next real challenge is how to use VoIP to drive profits.

E-mail me at CWilson3@telephonyonline.com.