[jrg]

"The conversion value is approaching zero" -- I think advertisers, some at least, have forgotten how advertising can work. They've been lead to believe by some that because they can track everyone's response to a campaign that it always makes sense to do so.

It's not likely that I'm going to see a banner advert on a page and immediately click on the link and respond to it. It interrupts whatever I'm actually doing - i.e. reading the content. But I might well remember having seen the advert later, and that might change my future plans.

(Here's an idea for free - make it easy for me to find the adverts I've already been shown. When I'm reading a physical newspaper or magazine I can flick back to the advert, or riffle through to find it again. Unless an advertiser is doing saturation advertising across an entire ad network one day, it's hard for me to do the same online.)

[Mcuban]

you may be right. But it doesnt change the reality that the destination site gets nearly zero benefit from the referral.