It is another defining moment for Wikipedia.

The public knowledge website is more than a decade old and remains among the top 10 Internet sites in the world, but some say it is becoming old and dowdy. Others want to keep it that way.

At the "Wikimania" event held in Washington held over the past week, several hundred members of the "wiki" community gathered for talks about the site and a two-day "hackathon," aimed at improving Wikipedia.

Some in attendance said Wikipedia, the free, open-source online encyclopedia which is largely unchanged from when it began in 2001, needs upgrading in an era where people are turning to social media like Facebook and Twitter.

"It looks like it's 10 years old," said Sebastian Wallroth, a software engineer from Germany.

Wallroth said it is difficult for people to collaborate and there are hurdles in uploading pictures and video, unlike more user-friendly sites like Facebook.

Semere Tazaz Sium, recent graduate of Virginia Tech in software engineering, agreed that Wikipedia "needs improvement from a user point of view."

"It's a very powerful tool but the user interface is a bit old," said the native of Eritrea who volunteers for Wikipedia.

Jimmy Wales, the Wikipedia founder who is still the public face of the project, said questions about the site's future direction will be worked out in the same manner the website operates -- collaboratively.

"I'm not the boss of Wikipedia, you are all the bosses," he told the opening session of Wikimania at George Washington University on Thursday.

Wales said that even forces are pushing Wikipedia in different directions, decisions won't be made in an "authoritarian" manner.

"We've always viewed ourselves as a community brought together for a particular mission. We have core value, like a free and open Internet," he said.

"The authoritarian model is not always the one that works."

Wales and others admit that Wikipedia needs to do more to encourage participation.

Wikipedia has editions in 285 languages, including growing editions in Yoruba, Swahili and Afrikaans, over 22 million articles and 100,000 active contributors. In some cases, Wales says articles are produced by "bots," or computer programs that automatically generate or translate content.

But Wikipedians, the name for those who participate, see an urgent need to make Wikipedia more open to newcomers, to keep up with the vast amount of information it is trying to process.

"It isn't always the most polite or friendly place," said a participant who goes by his Wikipedia name, Kudpung.

"Wikipedia is the encyclopedia everyone can edit, but you have to jump through a lot of hoops, and there is no welcoming committee. So people will create new pages and edit pages only to find those pages or edits deleted, and they are not told about it in a nice way."

Kudpung, a British national living in Thailand and longtime Wikipedia editor, said the site needs new people.

"It has been going for over 10 years and the number of quality encyclopedia articles has flattened out," he said.

"The majority being submitted are autobiographical articles that people post about themselves because they think it's Facebook. On the other hand, there are people who have something to contribute but they don't know the rules."

Sue Gardner, executive director of the Wikimedia Foundation which operates the site, said those involved in the project are aware of the slumping rate of participation and are taking to respond.

One initiative is a "visual" editor which will make it easier for people without special computer skills to contribute and edit Wikipedia articles.

"We want to make it as easy for people to edit Wikipedia as it is to update their status on Facebook," Gardner said.

She said devoted Wikipedians may want some changes but don't want it to become commercial.

"I think people really trust Wikipedia and one of the reasons they trust us is because we are honest about our mistakes. If we become slick and glossy I don't think that would become a source of trust."

Gardner said she and others are proud that the site has remained true to its ideals, and even "homely."

"Wikipedia is not flashy or splashy," she said. "It is not something designed by marketing people to keep you on to sell you something. So that is its charm."