Lots of debate arose around the fact almost 87% of Wikipedia editors are male. This is not necessarily true since the survey on which this “fact” is based has some biases (for example, people self-elected to answer).
However, a query run on the Wikipedia database showed that more than 83% self-identified as male.
While these numbers are not 100% representative of reality, it is probably true that most of editors are male. This is acknowledged also on a Wikipedia page about the systemic bias of Wikipedia (yes, I know this very page has been written by people whose bias we are trying to interpret but, going to the extremes, it’s turtles all the way down ;)

So the question could be: what is the ratio male/female on other social networking sites?

Just, for comparative reasons (and a bit for fun too), I compiled the following table based on the Social Network Analysis Report by Ignite Social Media. The table is sorted so that first lines are sites in which there are relatively more females than males. I’m not familiar with all the sites but it seems that sites more populated by women are the very social and playful (such as Haboo, Bebo, Myspace, Xanga, Facebook). On the other side of the spectrum there are sites populated most by males: sites showing what’s interesting right now thanks to social bookmarking such as Reddit, Digg, Identi.ca, and “professional” network sites such as Linkedin and Plaxo.
This table is not “scientific” in any way as well (for instance, percentages in the report are gathered from Google Ad Planner and Google Insights for Search).
Consider the following table just as more food for thought. Does it confirm your intuitions? Or should I say prejudices? ;)

	Social network site	Percentage of females
	Habbo	66%
	Bebo	62%
	Myspace	62%
	Xanga	62%
	Facebook	55%
	Ning	55%
	Hi5	52%
	Meetup	52%
	Tribe	52%
	Twitter	52%
	Yelp	52%
	Flixster	50%
	Foursquare	50%
	Friendster	50%
	Flickr	48%
	Last.fm	48%
	Livejournal	48%
	Metafilter	48%
	Multiply	48%
	Plaxo	45%
	Stumbleupon	45%
	Badoo	43%
	Mixx	43%
	Linkedin	40%
	Netlog	40%
	Newsvine	40%
	Plurk	40%
	Identi.ca	34%
	Digg	32%
	Indianpad	24%
	Reddit	24%

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