One marketing trick that I have seen more and more, especially from different discussion forums is people helping each other with StumbleUpon and Reddit and all the other social networking / bookmarking tools.
What they do is this:
They start a thread at the discussion forum or you can do it by sending e-mails to your friends in Internet marketing. You then tell them about a post you have published, and you ask them if they could help you to vote on it using one or more of the social networking / bookmarking sites.
You also tell them that you will do the same for them. They vote for you and you vote for them, this way you and your friends will have a much better chance to get more traffic for free.
At the moment, I can’t see any problems with promoting your blog posts like this and as far as I know this is “legal” at all the major social networking / bookmarking sites.
The only problem that I see, is for people actually surfing the sites… they won’t be getting high quality sites to surf, but sites to people with good friends. But on the other hand, if you only get the votes of your friends, your site / post won’t last that long at StumbleUpon or Reddit.
“The friends effect” will only get you inside StumbleUpon and Reddit, but the quality of your post will take you “all the way”. I have heard of people getting way more than 1,000 unique visitors a day from “the friends effect”.