If you’ve been curious about the money behind Facebook, today’s amended S-1 (PDF) filing gives us a glimpse as to what’s going on under the hoodie. The big deal? Q1 saw $1.06 billion revenues, $205 million in net income. Revenues are up from the previous quarter, which sat at $731 billion, but income is down slightly, from $233 million.

Tbe lower income number shouldn’t come as much of a surprise, as operating expenses have increased for the company during the past quarter, not including its massive purchase of Instagram for $1 billion in cash and stock. The revenue numbers are down quarter-to-quarter, but have increased sharply year-over-year from $731 billion in Q4 of 2011.

Now, about that Instagram deal? Facebook made the purchase for $300 million in cash, plus 23 million shares of stock. Oh, and there’s a breakup fee. A rather hefty one, actually.

The site is also boasting some non-monetary numbers that are impressive. Namely? 901 million monthly active users. That means an average revenue per user of $5.11 in 2011, up from $4.08 in 2010.

The refreshed filing comes hot on the heels of the news that Facebook is paying Microsoft $550 million for a number of patents that Microsoft recently acquired from AOL. Whether Facebook intends to use the patents offensively or defensively remains to be seen, but there’s no downplaying the importance of the acquisition.