The problem isn't advertising banners, it's the audience. The people that tend to click on banners and such have all gravitated to the social networks.

You can still make money that way, but it's not going to be like it was a few years ago. Advertisers aren't stupid. They're going to put their best and highest-paying creatives where the audience is hanging out and the audience isn't hanging out at blog sites anymore.

The subscription model isn't going to work, though it may take a few months for Medium to figure it out.