It’s not like we were unaware that Facebook was approaching 1 billion monthly active users. In their original S-1 filing at the beginning of February, they told us that they had 845 million MAUs, which obviously makes it the biggest social network in the world. But today they updated their S-1, and in it are some stats about where they’ve come in less than three months since the initial filing.

And as of now, Facebook boasts 901 million MAUs.

Doing the math, that’s +56 million users in about 11 weeks. We can in no way predict that the growth rate of Facebook will remain at a constant 56 million users per 11 weeks, but let’s just imagine it does, just for fun. In that case, we can expect them to hit 1 billion MAUs well before the end of the year – sometime around early September.

Facebook also dropped some additional stats. Users now generate 3.2 million likes and comments per day, up from 2.7 million in February. Total friend connections across the network has jumped from 100 billion to 125 billion. And there are a staggering 300 million photos uploaded every day.

On the financial side of things, Facebook made $1.058 billion in revenue in Q1 of 2012. That’s up nearly 45% from Q1 2011, but down just a bit (6.5%) from last quarter. Advertising accounted for $872 million of their Q1 2012 revenue.

According to recent eMarketer figures, Facebook’s growth rate is declining, which isn’t really surprising considering how many users they already have. By 2014, it is expected to slow to 3.6%.

Their much-anticipated IPO is expected to come in May, with the latest speculations pinpointing May 17th as the exact day.