II can tell you now that I've never clicked through on any FT ad. Granted, some of these may be pay by impression, but, you're not making any money off me. I'd gladly pay FT some monthly subscription fee and skip the ads.

Now without doing clickstream anaylsis, I'd suspect that the more frequent users of FT are the least likely to click through on a web ad, whereas the casual passer-by would be more likley to click through.

Therefore, if you offer a subscription-based, ad-free version, FT should be able to increase revenues with minimal impact on the click through rate.

Then again, I may be 100% wrong, but it sounds good to me.