Since VoIP telephony and all the associated services first hit the market, forecasts have been bullish. Looking back, some of the forecasts were way underestimated and over the last few years, adoption has grown even further. Back around the 2004 timeframe most estimates placed the North American VoIP subscriber base forecast for 2010 at approximately 18-20 million. By the time we got to 2007 most forecasts had increased and at least one had 2010 pegged for over 40 million subscribers. In the early part of 2010, with the year already started, multiple prognosticators had global estimates for the year just pushing past the 100 million subscriber mark. Now with the benefit of hindsight we can look back and see where we really ended up. According to a report released by Infonetics Research at the end of March 2011 (VoIP and UC Services and Subscribers), the number of residential VoIP subscribers increased in 2010 to reach 157 million worldwide. The report also predicts continued growth for the next 5 years, with overall service revenue to double during the same period.