True, but what worked for Facebook/Zynga will not necessarily work for Joe's homepage/Heyzap. Facebook is a destination for people to socialize and sometimes p

True, but what worked for Facebook/Zynga will not necessarily work for Joe's homepage/Heyzap. Facebook is a destination for people to socialize and sometimes play with their friends, so games there are complementary goods. Most other sites (news, personal finance, technical documentation etc) have different objectives, and it's not clear why games will be complementary.