Well, it's about time
Below are the targeting options. Currently, it's only available for the Site-Targeting campaigns.

* Gender
o Female
o Male
* Age
o 18-24
o 25-34
o 35-44
o 45-54
o 55-64
o 65+
* Annual Household Income (USD)
o 0-14,999
o 15,000-24,999
o 25,000-39,999
o 40,000-59,999
o 60,000-74,999
o 75,000-99,999
o 100,000+
* Ethnicity
o Any
o White/Caucasian
o Black/African American
o Asian/Pacific Islander
o Hispanic

Children
o Children in household
o No children in household.

I tried using it but it just doesn't work as effectively as keyword-targeting for me. Our forums require a certain level of expertise about the industry in order to participate.

Haven't played around much with Adwords Demographics. Dani, are you sure the data comes from comScore? Read somewhere that the data comes from user registration info.

That's what the Google FAQ said Didn't get that out of a third party.

Does google plan to roll out the same feature for the search network?

It is rumored that both Google and Yahoo are working on similar demographic targeting as MSN adcenter currently offers.