When I talk with small-business people, many who are skeptical of social media — particularly Baby Boomers — often talk about how social sites are just meant for the young. And some say they think spending a lot of time online is unhealthy and antisocial.

I try to show them that people of all ages are adopters of social media. Facebook alone has had dramatic growth this year at nearly all age levels, none more pronounced than women over 50.

Now there are new numbers available on social media users. The median age of a Facebook user has now risen to 33, seven years older than in May 2008. That’s not far behind LinkedIn, the business networking site whose 50 million-plus users have a median age of 39. The median age of a Twitter user has dropped to 31, which shows that Generation Y, which was not an early adopter, is now turning to the microblogging service. There had been numerous articles earlier in the year that Gen Y thought Twitter was pointless. Apparently, that’s changing.

Facebook getting older? Twitter getting younger? What does this mean? It means the old adage is no longer true that only the young are the early adopters of technology. And new social sites designed to attract the young away from Facebook and Twitter are reportedly not having an impact. The young are willing to use the same social media now used by their parents.

So much for age creating a digital divide in social media. (Yes, MySpace remains decidedly young — a median age of 26 — but its focus has shifted to mostly music and entertainment. And it’s certainly not the dominant influence it once was.)

While we’re debunking myths, let’s burst another bubble. Remember the study which found people were becoming more socially isolated because of technology, especially mobile phones and the Internet? Not so fast, according to a new study from the Pew Internet & American Life Project. Pew found that these technologies do not have a harmful social impact upon people.

In fact, Pew found social networking sites provide an outlet for “discussion networks that are more likely to contain people from different backgrounds.” In other words, people have digital contact with a more diverse group of people.

Boomer business owners, isn’t that one of your company goals? Don’t you want to expand your reach to new people, new contacts outside your regular sphere?

Can’t wait for the next business owner to bring up age, or dismiss the merits of social networking. I’ve got some new research to share.