Yes, both are huge communities and can deliver a tremendous impact. Just having a Twitter following or a Facebook page substantially elevates one's coolness factor. The vast reach of both services touches not just thumb-typing youth, but people of all ages and from all walks of life. The good news: Joining Facebook and Twitter is easy and doesn't cost a dime. The bad news: They can suck up time and energy faster than a 426 Hemi-powered Dyson vacuum. Unlike blogs where a posting or two each week is fine, Facebook and Twitter devotees have far higher expectations.

Fail to keep these social media sites fresh and your personal brand can quickly go from “cutting-edge” to “dull as a stick.” Then there's the time needed to protect your Facebook page from spam and unwelcome or inappropriate postings from strangers, competitors and friends. These sites are not for the weak hearted — or the time constrained. I've talked to my clientele and they aren't using either Twitter or Facebook for business. So for me the decision was simple and I haven't signed on to either.

Determining whether these platforms make sense for you isn't hard. Simply ask your clients whether they tweet or have a Facebook page. If so, ask them if they use these sites for business or for personal interests. Within a dozen conversations you'll have a sense of whether the time, devotion and energy required by these platforms is worthwhile for you.

Then keep on asking. People's use of social media evolves over time. If your clients are heading onto Facebook you want to be there to greet them. Because when prospects ask if you're talking to them, you want the answer to be a clear and resounding “Yes.”

Alan Katz is principal of the Alan Katz Group and author of “Trailblazed: Proven Paths to Sales Success” (www.TrailblazedSales.com).