Yahoo, like google never pays for images.  last time I heard about from yahoo (couple of years back) they were asking permission though

lol, how noble !

en serio, that's where every one is going actually, Phil.
there has to be big money in taking advantage of contributors to rip them off with free images.
this is why the Big 6 is so much in pushing free free free images and if not free, as good as free
.. ie. low low low prices of subscription images.

there is no lost of money on the side of the Big 6 for aiming in this direction.
they make money with or without the buyers paying for our images.
they can make probably as much, if not more money, simply on bringing traffic like google,
and all those sites luring desperate single men and women to join and find their dream mate,etc.

this is the direction we are headed, if we are naive enough to believe and say,
"oh, it's okay, i don't complain how low they sell my images, as long as they make it up with more downloads and earn me the same amount of money each month".

that to me is amazing how idiotic some of these contributors are .
maybe what we need is to send these goons back to primary school to learn their arithmetic.
eg. if one apple costs $1 how many dollars do you need to buy 10 apples.

then send them off to another primary class to teach them Economics.
supply and demand.
if you let too much supply into the market place, the demand will even be diminished, or more importantly to the wallet, your  profit margin  will drop towards the bottom, UNTIL THERE IS NO BOTTOM LEFT.

look on the bright side (for the Big 6 's own selfish interest),
if our images are free, then magic genie, there will be no more worries
about image theft.
you cannot steal what is free to take.

isn't that a miracle for us? the problem of image theft is solved once and for all.
 

not relevant but does make me think of urban myth of the guy put a fridge out the front yard with a sign saying "free" and after 3 days of noone taking it he changed the sign to for sale $50. Someone stole it that night. When it was free it must be no good

Not Urban Myth, Phil.
That same guy who stole the fridge started his own micro stock agency many years later 

That's why they don't go after stolen images 

They using a watermarked image from Istock
With original metadata

http://www.flickr.com/photos/cafecathi/

Kone