If you're one of those people in the UK games trade that thinks there is nothing to learn from Facebook games, then think again.
The social networking site hosted one of the GDC opening keynotes today, showing how social features and identity sharing is changing the way games are designed - and how Facebook is reaching hundreds of millions of people every month.
Facebook's popular Platform and Connect development tools are already integrated into a raft of consoles, including DS, 360 and PS3, and are driving a huge 'mass audience' online - 200m people a month - to play games supported by the social networking site.
"Facebook is at the centre of a people powered social web," said platform manager Gareth Davis. It's hard not to disagree. The site has 400m users a month, 200m a day logon for sessions lasting around 55 minutes each.
In tandem with this there are a million devs making Facebook Platform Apps and using Facebook Connect.
Games are one of the most popular parts of the social networking service with 200m playing games on Facebook each month.
"We have a mass audience," said Davies. "We have moved beyond the core games consumer and have people playing games across every demographic."
And this boom means "Facebook games are changing our games are developed, designed, monetised, distributed operated and supplied," said Davies.