Affiliates - Do they work? For whom do they work?

I went to the SFIMA event this evening to learn about affiliate marketing. It was not a great presentation. Terrible in fact. Power point slides circa 1990.  Long lists of obvious points, no interesting analysis or illustrations. Really a shame.

Afterwards, I cornered CPMdirect's Co_Founder & Managing Director.  MY question, in what cases do affiliate pulishers make more money on affiliates than they would with Google ads or CPM advertising?  There was no clear answer to me. I couldn't get any clarity on why and how affiliate marketing would make sense for a big web publisher like me.

Gus Brito, the head of CPMdirect, made this point. He was previously the head of marketing (or something like that) at TigerDirect, Comp USA, and Circuit City.  Back there, affiliate marketing was larger than the affiliate or SEO marketing department.  His point was that affiliate marketing really worked at Tiger Direct.  I still don't really understand the significance of the point.

Did affiliate marketing reign because of the payment cycle in some way?  For instance, is the payment cycle by affiliates slower so the TigerDirects, to whom payment terms and cash flow are so significant, loves it?

At the end of tonight, affiliate marketing appeared more sketchy, more sleazy, more opaque, and less professional than it ever did before.  Goodnight affiliates.