After years of socializing, Facebook and MySpace mean business. The sites, which started as a way to help people stay connected with friends, in the past year have begun catering to professionals, offering networking and advertising opportunities.

Some companies are embracing the trend, while others are trying to shut the Internet's virtual doors as firmly as possible.

Barbershop owners Erin Portman and her husband, Michael, of Austin, Texas, created a page on MySpace.com, the site owned by News Corp and especially popular with teens.

MySpace friends of Bird's Barbershop often post photos and comments about their haircuts on the music-filled MySpace page, with links back to their own personalized MySpace pages.

We started collecting 'friends' before we were even open, Portman said. I definitely think it has boosted our business. The shop now has more than 2,100 MySpace 'friends,' many of them customers.

MySpace rival Facebook.com, started up in 2004 and in 2006 opened registration to people with corporate e-mail addresses. Thousands of business networks and communities exist on the site among 32 million users, with much of the recent growth attributed to professionals.

Facebook says its fastest-growing demographic is people older than 25. It's chief executive is 23-year-old Mark Zuckerberg, who is also one of the founders.

While many businesses are using the sites, employees taking advantage of them during work hours are stirring up controversy.

More than two-thirds of London businesses have banned or limited employee access to the sites, says a straw poll commissioned by Britain's Evening Standard newspaper in July. The United States, the United Kingdom and Canada have the largest number of online networking users, according to Facebook.

Toronto prohibited its 40,000 municipal workers from using such Web pages three months ago, saying it distracts them.

We want to ensure that city workers who are paid by the taxpayers are not wasting undue time on non work-related activities, said City of Toronto spokesman Brad Ross.

NOT SAFE FOR WORK

Many companies block inappropriate Web sites such as pornography from their computer servers. Some even monitor their employees' online activity.

Some networking sites allow users to post photos and videos, which may be deemed NSFW -- not safe for work -- on the Web.

But Jerald Jellison, a professor at the University of Southern California in Los Angeles, and an expert in change management and social relations, said companies should embrace networking.

People who lead businesses are reluctant to acknowledge the extent to which hard-working professionals do other things besides strictly working, he said. We're human beings. We socialize. It's going to go on whether you allow it or not.

People often meet other employees of their own firms through the sites, said Jellison, who argued that such connections could be used to share resources and increase productivity.

If there is somebody who has experience dealing with clients in a particular company and I find someone else who has done business with this company, I could get information from him, which could help in terms of making a sale, he said.

International Business Machines Corp. has developed networking software designed for business clients to do just that.

We tailor it to specifically help people organize their own activities, said IBM's Vice President of Emerging Technologies, Rod Smith. The more you're isolated and not in the loop, it makes it tremendously hard to really define your work.

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