If I were to use one thing to earn money online, it would definitely be earning through affiliate programs, such as Amazon Affiliates. The thing about earning from a blog, is one of those things that isn't so definite. Most people think that if they setup something that they think is a great idea, even it is a great idea, they will not always get popular, and will not always get money rolling in from it. I don't think money is drying up, just more along the lines of too many people thinking that they will get the traffic they think they deserve, that would give them that money they think they will earn. Otherwise know as doing nothing for something. I am a big advocate for working to earn. Most people don't realize how much work is needed, in order to earn successfully from a personal blog.