Today is a huge milestone Facebook. Now at 500M users, Facebook is the largest social network, with the closest runner-up, Twitter only at 100M users. With 400M people separating the first and second social networks; is Facebook simply too big? Telegraph.co.uk has some interesting statistics on the site's usage:

People spend over 700 billion minutes per month on the site.

An average user has 130 friends.

There are over 900 million objects in total that Facebook users can interact with, such as community pages.

The average Facebook user is connected 80 pages, groups and events.

The average member creates 90 pieces of content each month.

More than 30 billion pieces of content, like photos, web links and news stories, are shared each month.

About 70 per cent of Facebook users are from outside of the US.

It took five months for Facebook to attract an extra 100 million users, from 400 million to 500 million.

Last January Facebook only had 150 million members.

So what's the secret? We'd like to hear what you think.