I have a vested interest in "Ecommerce", since I sell software over the Internet.  I think plenty of folks who try to monetize websites with advertising might want to try selling something of value instead. 

I'd have to make $80 CPM to equal the profits from my software business, and this is in a niche with a typical CPM value of about 90 cents to $2.  (I should know, I pay lots of other sites that much to send me their visitors so I can make $80 CPM off them.)

I recently opened up a free webapp in the same vertical.  My friends asked "So, when are you going to put AdSense on it to make money off that sucker?"  I think the day after "never" -- I'm going to cut out the middleman and use the free site to drive visitors to the site selling the software.  Then I get oodles more than the going rate for AdSense clicks (~8 cents each in my vertical) and I don't have to share any of it with Google.  (When I pay some publisher ~8 cents to plug my product they only see ~4-5 cents of it.  The rest inflates Google's bottom line.)