Some advertisers are using Facebook ads much like they would Google adwords.
Facebook is great for brands that are about experiences, events, interests, passions and beliefs. Businesses that are more corporate or factual do not fit at as well.
In other words, people are in a different state of mind when they use Facebook than when they use Google.
How do you know if Facebook is right for you? One way is to answer the questions Perry Marshall set up at IsFBForMe.com.