Ian. Just posted on His Blog (www.liesdamnedlies.com) more about Gatineau and how they get the data on age and gender, Btw Ian was supposed to be at Adchamps Europe but Justin Carder stepped up and was pretty awesome I would have to say.
Anyway from Ian’s Blog.
the answer is that we do get this information from users’ Live ID (formerly known as Microsoft Passport) profiles, but I would stress that we get this information anonymously, and there is no use of PII (Personally Identifiable Information, such as name or e-mail address) in the product.
Which Is pretty cool IMO, As an Advertiser I want to get more bang for my Dollar, not just say here is my money go spend it.
and If you outsource your web advertisings to an agency, ask them if your ads are getting age and gender targeted, In fact ask if they have even set-up the account in Live and Yahoo, you will be surprised how many agencies just don’t give a fuck about you !!!