A great question came up at Cre8asite Forums asking;
If I essentially give away bandwidth so that sites A, B &C are displaying a GIF or a Flash file that's remotely hosted on my site, does this potentially amount to an SEO benefit?
So, if I take an image from your site, but decide to call the image directly from your site. I.e. I do not copy the image from your server over to my server, but rather I just link to the image source on my page, does that count towards link popularity or provide any ranking benefit?
As anyone with HTML knowledge knows, to call an image from any site you just use the following code
<img src="http://www.domain.com/pics/imagename.gif">
So does that code give any power to the site the image is being called from?
Ammon Johns said that it used to back in late 2001. He explained that "One could take 2 domains, and show images on one that were located on the other, to gain a cross-linking benefit that apparently bypassed all of the cross-linking checks and filters."
But he said it was most likely an oversight then by the search engines. Simply, if you think about it, many affiliate and other types of tools uses hidden image files, hosted on a 3rd party server, to track hits and impressions. So the value of allowing people to host an image off your server is no longer as important or at all important to a search engine.
EGOL remarks that there may be some perceived value to someone pulling an image from your server. He explains that "in some ways these are votes for your domain and in other ways it is simply mooching BW."
So it is not black and white but typically, I doubt search engines will use hosted images as a link popularity factor without being able to differentiate the difference between a image used for a "vote" reason versus a tracking or other "mooching" reason.
Forum discussion at Cre8asite Forums.