How many words an hour does your kid hear?

I read an interesting article in the Economist about Marriage in America.  But the quote that really peaked my interest was the difference in the number of words children from different types of homes heard in an hour:

One study found that a college professor’s kids hear an average of 2,150 words per hour in the first years of life. Working-class children hear 1,250 and those in welfare families only 620.

My grandmother told me I was going to talk her ear off when I was little – I guess that’s what comes from having two parents as teachers!