The LAO released a curious document this week. They’ve been doing a lot of thinking about Facebook. On the one hand, who doesn’t spend a lot of time thinking about Facebook? But they’re doing it during working hours, unlike all of you, no doubt.

They’ve been wondering how much this week’s IPO means in revenue for the state. Turns out it’s not nothing. In fact, it’s shocking.

The LAO estimates that fully one fifth of 2012 personal income growth in California, and one percent of all personal income in the state in 2012, will relate directly to Facebook’s initial public offering. The IPO will result in well over $10 billion of income for California residents.

They rely on a lot of variables, of course: share price now and later, how many shares people sell when, how many of the people live in California, etc. If the Governor’s initiative doesn’t pass, the state would see a few hundred million less than estimated. If the chief recipients of this manna from Zuckerberg act differently than expected, the 2012 revenues could come in a few hundred million dollars higher. But any way you slice it this is astonishing.

And don’t forget that people, a few people anyway, will have an extra $10 billion or so lying around, so there will likely be effects on property taxes and sales and use taxes that defy accurate estimation.

In less serious news, the LAO today released their overview of the May Revision, which finds that the Governor’s revenue estimates are generally reasonable and that many of the proposed cuts have merit, but that there are some alternatives the Legislature should consider. (“Reasonable,” “has merit,” and “alternatives” are three of the LAO’s favorite phrases.) They do think the Governor’s estimate of the revenue flowing from dissolved redevelopment agencies faces great uncertainty.

This is the state budget, after all, so nothing is certain.

But I bet Mr. Zuckerberg gets a nice thank you card from the Governor.