In the last five years the social networking sites, online places where a user can create a profile and build a personal network that connects him or her to other users, have rocketed from a niche activity into a phenomenon that engages tens of millions of internet users.And it seems that Yahoo is ready to get in the game.

It all started on Tuesday with an e-mail received by the New York Times’ journalist Brad Stone from an Yahoo employee. When Stone tried to open the link sent in e-mail to visit the profile set up for him by the Yahoo employee, he couldn't get past a login page.

“I followed the link to mash.yahoo.com, which bounced me to a username/password page, titled Yahoo Guesthouse, where my Yahoo login information did not work. I pointed this out to the Yahoo employee, and he replied cryptically over e-mail: “Yeah, I jumped the gun on inviting you. Not yet open to the public… Soon…”” wrote Stone on his blog.

One hour later Stone received another e-mail, this time from a a senior Yahoo spokeswoman who said that the Yahoo Mash is real, but its in an alpha phase and is currently tested by Yahoo employees.

Few days later on Friday the company launched the Yahoo Mash’s official blog and has started to invite people to test it.

“We just started inviting our friends outside Yahoo! to join us in testing Mash: a new approach to online profiles. If you’ve used other online profiles before you’ll feel at home in Mash. But there are some new twists that make things a little interesting and, we think, a lot of fun.

1. You can make starter profiles for your friends. Think: “first round’s on me.”

2. You can leave your profile open to contributions by trusted friends.

3. You can customize your — or your friend’s :) — profile with modules from a growing gallery of apps.” wrote Will Aldrich on the Mash’s blog.

It’s still unclear how Yahoo Mash will coexist with Yahoo 360 social network, which was launched by the company in March 2005. Is Yahoo Mash just a different service or in time those two social networks will be combined into a new one?

It seems pretty early to anticipate what Yahoo will do next, because Mash, as Aldrich pointed on the company’s blog, “Mash is still pretty raw--there are bugs and we haven't gotten to several of the features it really should have”

According to the people at TechCrunch.com who got the chance to test the new service, Yahoo Mash has “features common to Facebook, MySpace, and My Yahoo.”

“You can load a set of modules onto your profile page and move them around drag-and-drop style. The modules include Flickr RSS, Ego Boost, Common Friends, MyMoshLog2, Blog Module (RSS 2.0), Asteroids, Astrology, PimpMyPet, Hover, Kaleidescope, Guestbook, and My Stuff.” said Mark Hendrickson in his review.

The news about Yahoo Mesh has emerged shortly after Yahoo announced that its UK and Ireland division will sell Bebo's display advertising. Bebo is the number 1 social networking site in UK and Ireland and, according to the data released by comScore Media Metrix in July 2007 it has a monthly audience of 11.6 million users. Yahoo and Bebo announced also that Yahoo Answers will be integrated into Bebo's and the development of a new Bebo Toolbar.

For Yahoo is the first time when is working with a social networking site. Maybe, in the light of the new Yahoo Mash announcement, Yahoo is ready to learn something new from Bebo? We’lll live and see!