According to TechCrunch's Eric Schonfeld in liveblog from New York City, Facebook is announcing three things:
1. Social Ads (ads targeted based on member profile data and spread virally)
2. Beacon (messages in feeds), and
3. Insight (marketing data that goes deep into social demographics and pyschographics
which Facebook will provide to advertisers in an aggregated, anonymous way). These three things together make up Facebook Ads.
Social Actions + Content = Social Ads