If you're into Article Marketing solely for SEO benefit, it pays to check whether or not the contextual links you create have this attribute added to them. If they do, look to publish your articles elsewhere.
If you contribute to forums to receive SEO value, you'll also want to check and see whether or not your signature has 'nofollow' added to it. If it does, you're wasting your time (from an SEO perspective).
How to check for the 'nofollow' attribute:
You need to view the page source. That's the HTML code that makes up the page. If you're a Firfox user like me, you can do that by pressing Ctrl U. The page source will appear. Internet Explorer users need to navigate to the 'View' menu and click on 'Source'.
Find a link by pressing Crtl F (Firefox and IE) and entering this into the search box: href=
This will take you to the first instance of an anchor tag. Look either side of the href= and see whether the nofollow attribute appears: rel="nofollow"
Here's an example of a full HTML tag so you can see how it looks...
<a href="http://asureimage.com/" rel="nofollow">Lead Generation</a>In the above example, the text 'Lead Generation' would be clickable in a web browser. Normally, this would be a contextual link back to my main site and provide me with link juice. Unfortunately, in this case the 'No Follow' tag tells Google not to transfer any link juice to my site.