[rm999]

Facebook reported in their SEC filing that they had 170M active US accounts, about 55 accounts for every 100 Americans. Interesting gap, especially because this survey only looks at US internet users and doesn't ask about active.

I wonder if this is due to multiple accounts per person, bad facebook reporting, or bad survey results.

[libber]

One wrinkle - Doesn't this poll ignores anyone under 18? Facebook lets you sign up only once you have turned 13. Internet users between the ages of 13 to 18 are unaccounted for.

[diego]

I trust the tool, and I'm pretty confident in the margin of error. I would bet that there are a significant number of people with multiple / fake accounts.

[bslatkin]

Most people I know have a FB account for their dog. Is it just me?

[sharkweek]

I have a couple accounts -- one for work, one for friends, etc -- I know they have a way of breaking up who sees what on one account now, but I created these accounts a while before that product released