In a study released yesterday, the Nielsen Company reports that over the past year Americans have increased their time on social networking sites by 43 percent, while their use of email has declined by 28 percent. The survey found that 40 percent of American’s on-line time is spent on social networks (22.7%), online games (10.2%), and e-mail (8.3%). In 2009, these three activities comprised just under 37 percent of on-line time.

In 2010, Americans spent 22.7% or just over 13 1/2 minutes per hour of their on-line time on social networking and blog sites, compared to 15.8% or 9 1/2 minutes per hour in 2009. On the other hand, in 2010 instant messaging and email had a combined share of 12.3% or just under 7 1/2 minutes per hour compared to 2009 when the two accounted for 16.2% or just under 10 minutes per hour. Though email and instant messaging are still two important communications channels, it would appear that the use of Twitter, LinkedIn and Facebook messaging is increasing.

Another important finding in the survey concerns mobile internet time versus internet time on computers. Though mobile web users have increased their social networking behavior by 28 percent, email activity is still the dominant web use accounting for 41.6 percent of mobile internet time in the United States.

Consequently, the study concluded that even though computers and mobile phones are converging technologies, “mobile internet behavior mirroring its PC counterparts is still some way off.”

So what does all this mean? Clearly social media is becoming a major platform for communication. With newer smart phones providing easier access to social networking platforms, we will see mobile internet time increase on Facebook, Twitter and LinkedIn and other social media sites. Increasing numbers of users will be able to regularly check for status updates and tweets while standing in line or walking down the street. Therefore, if you have a timely and important message to convey, which communications channel do you employ? Radio is still an important medium during drive time, television will certainly maintain its value during prime-time, but what medium should you be considering the rest of the 24 hour cycle?

If the public likes your Facebook page or is following your tweets, clearly there is an opportunity to connect with them on a 24 x 7 basis. If you are candidate or consumer brand, advertising on YouTube or Hulu becomes increasingly important since larger numbers of voters and consumers are using the Internet to access their favorite shows and clips. If you want to successfully deliver your message today, you need to identify where your audience is, and figure out how and where to engage them.