Maybe Microsoft's multi-billion dollar deal for Skype wasn't such an outlandish deal after all. Because according to a recent poll conducted by the Pew Internet and American Life Project, the popularity of Internet phone calls has jumped dramatically, with 5% of Internet users placing a VOIP phone call on any given day.

The survey found that almost a quarter of American adult Internet users (24%) have placed a phone call online. That's 19% of all American adults.

That's a marked increase from the last time the Pew Research Center polled people about VOIP usage. In February 2007, just 8% of Internet users (roughly 6% of all adults) had placed phone calls via the Internet, and 2% of Internet users were making VOIP calls on any given day. The Pew Research Center says that it has asked these questions at various times throughout the past decade and never has that daily figure risen above that.

But clearly something has shifted.

The research found little difference between men and women when it came to making calls over the Internet. However there were some differences based on socio-economic factors. Internet users with higher levels of education and household income were more likely to use the Internet to make phone calls, as were those who live in urban areas. Hispanic users were also more likely to use VOIP services than others - 27% compared to just 21% for non-Hispanic Whites and Blacks.

The Pew Research Center does admit that they rephrased the question in this round, which may account for some of the increase: "Please tell me if you ever use the Internet to make a phone call online, using a service such as Skype or Vonage? Did you happen to do this yesterday, or not?" This was the first time that the organization specifically referred to Skype when surveying about VOIP usage.

But even if the mention of Skype triggered a more affirmative response than in previous surveys, there's little doubt that placing phone calls over the Internet has become more popular. Pew points to several reasons why this is the case: "It is free or cheaper than other types of phone calling; it is enabled on many handheld devices like smartphones and tablet computers; more and more meetings and classroom activities exploit online phone connections along with video capabilities; and more families and friends are building online calls into their communications streams."

The increasing popularity of video calling is also part of the appeal. In this latest survey, the Pew Research Center found that 7% of cell phone owners had participated in video calling using their mobile devices.