As we now have members who pay not to see ads, and guests who do see ads, which is more profitable for the SD: membership fees, or ad clicking?
In theory we want the rates to be such that the guest/membership choice is revenue-neutral. In practice it depends on the ad mix, which varies from week to week. At the moment, to be frank, we probably make more money on fees. (To clarify, we don’t charge advertisers per click, but per impression.) We’re starting to get some ad buys at better rates and hope to be at the revenue-neutral point soon.