I had the pleasure of spending Wednesday night at my first Digital Directors’ Dinner event, hosted by Netimperative and BIMA, which welcomed Stephen Haines from the UK Leadership team at Facebook.

Needless to say, on what was – as it transpired – the eve of Mark Zuckerberg’s announcement that Facebook had exceeded 350million members, there was plenty to talk about.

I won’t share the specifics here, as attendees of the event agreed to a ‘within these four walls’ code of conduct, but what I found even more interesting than the fact that 83 of the top 100 US advertisers have switched their marketing budgets to Facebook, was Zuckerberg’s obvious and continued commitment to the core Facebook values – ‘open’ and ‘connected’.

By having a clear idea of what his values were from the outset and by having stuck by them, Zuckerberg has built an organisation that is true to its core.  Using these values to shape decisions about both technological alterations (for example, this week’s announcement about privacy settings) and business transactions, has meant that Zuckerberg’s original vision has not been diluted as a result of growth.

And when you consider thatFacebook has accelerated from zero – 350million users within five years, that’s some impressive feat.