Men talk about as much as women

Are Women Really More Talkative Than Men?
Matthias R. Mehl, Simine Vazire, Nairán Ramírez-Esparza, Richard B. Slatcher, James W. Pennebaker

Women are generally assumed to be more talkative than men. Data were analyzed from 396 participants who wore a voice recorder that sampled ambient sounds for several days. Participants' daily word use was extrapolated from the number of recorded words. Women and men both spoke about 16,000 words per day.

That's the abstract of this paper in Science. Since the paper may be behind the firewall, you might want to check out the commentary by Nikhil Swaminathan in the Scientific American:

[James Pennebaker's] device, called EAR (for electronically activated recorder) is a digital recorder that subjects can store in a sheath similar to a case for glasses in their purses or pockets. The EAR samples 30 seconds of ambient noise (including conversations) every 12.5 minutes; carriers cannot tamper with recordings.

Researchers used this device to collect data on the chatter patterns of 396 university students (210 women and 186 men) at colleges in Texas, Arizona and Mexico. They estimated the total number of words that each volunteer spoke daily, assuming they were awake 17 of 24 hours. In most of the samples, the average number of words spoken by men and women were about the same. Men showed a slightly wider variability in words uttered, and boasted both the most economical speaker (roughly 500 words daily) and the most verbose yapping at a whopping 47,000 words a day. But in the end, the sexes came out just about even in the daily averages: women at 16,215 words and men at 15,669. In terms of statistical significance, Pennebaker says, "It's not even remotely close to different." He does point out that women tend to jaw more about other people, whereas men are apt to hold forth on more concrete objects—so the stereotypes of ladies as gossips and guys engaging in car talk can live on.

Here's the NYTimes story.