Mark Zuckerberg greeted by standing ovation at pre-IPO hackathon [PICS]

It’s finally here. Today is Facebook IPO day. You might think that Mark Zuckerberg would be kicking back in his hoodie and slippers. You’d be wrong.

Instead, the Facebook CEO was on hand to launch the company’s 31st hackathon — aimed at building brand new Facebook products.

When Zuckerberg arrived at the marathon hacking session at Facebook HQ in Menlo Park California, he was greeted with a standing ovation.

Facebook staffer Francis Luu posted these some great pictures of the event. We’ve chosen a few of our favourites, but you can check out the rest on…well, they’re hardly going to be on Picasa are they?

The hoodied one will ring the bell to open Facebook’s trading from its California headquarters.