Online magazine Salon's share of revenue from ad sales has grown to eclipse revenues from the subscriber fees it initially based its business model on, according to ClickZ.

Salon serves ads to non-members and non-premium members before displaying an article the reader has chosen. Premium subscribers pay for an ad-free experience, a privilege that has cost $30-35 a year but will go up to $45 in March.

Based on the current fee structure, it's estimated that Salon makes some $1.5 million dollars a year from premium subscribers. Ad revenue for the fourth quarter of 2006, on the other hand, was reported as $2.2 million.

The site has shifted business models before, first experimenting with a Premium Day Pass that would give non-subscribers access to the site in exchange for viewing an ad. It has also presented non-members with the option of either subscribing or viewing an ad for free access.

Now all non-subscribers are automatically shown an ad before being redirected to the article they've chosen.