"You reach that moment where you realize: a) I can't keep up with every update and b) I don't want to," Musciano says. "You learn to skim--the same way you'd skim a headline in a newspaper or glance through 50 e-mails in your inbox."

Musciano sorts his followers for easy scanning with the . And by linking his Facebook and Twitter accounts, one update appears in both places. "You can waste a lot of time if you don't have the right tools," he says.

Cornell suggests very active social media users . "Limit the amount of time you spend on the sites--build it into your calendar if you have to."

For those like MacKay, who may be struggling to understand the value of time spent on social media sites, Cornell recommends treating each source like an experiment. "You're not sure when you start something how much value there is in it. Find some metrics--how are we going to measure the value?--and then reevaluate it a little bit down the road."

Knowing when it's time to walk away from a site that's not serving your needs is also important. "We don't block sites like Facebook and Twitter, but I have a lot of concerns about how much bandwidth is being gobbled up and the amount of socializing going on in the workplace," says MacKay. "I think there's a little more value with LinkedIn and other ." And the value he derived from dabbling has even transferred over to his workplace: MacKay is currently working on developing an internal social network for the AMA's members.