Good netiquette demands that you credit artists for their work.
I included a stock photo in a snide little post called "Reason's Greetings" with a Christmas scene photo. Realizing that the artist may not share my opinions and would dislike having my page show up in a google search for his name, I decided that a better way to credit the designer would be to create a separate page with microstock credits. This page has links to the designer's microstock page, and a link back to my project.
On the SE0 side of things, good netiquette happens to make an inbound link back to my blog post.
I designed this Microstock crediting program for my own use. I decided to make the program open to the public at large. I invite anyone using MicroStock in blog posts to use this program. It is simple: You enter basic info about the picture and your project. That info creates a page. To credit the graphic designer, you simply add a link to the credit page. As there is a link back to your page, this process is beneficial to both you and the graphic designer.
NOTE, the program is intended to credit designers for their work. I will delete entries of people who fill up my database with spam.
If you happen to be a photgrapher or graphic designer, Scott Maxwell created the following graphic to explain the overall MicroStock process. (Clicking the image brings you to the "Microstock Credit Page," which links back here.)