Here are some of the social media articles that became popular This one was tough as I have written on many twitter applications, Linkedin Apps etc only to find a new application after a few months. But change is the nature of the game especially if you want to stay online.
1) Spreading content on social media
http://www.decisionstats.com/2009/05/25/spreading-content-using-social-media/
My philosophy is stuff that you do not need to keep secret, should be shared with as wide as audience as possible. For this reason, I prefer that I meet the reading audience half way, on Facebook, Linkedin, Twitter rather than play the same old come to my website if you want to read it game. If you love your content, let it go free. The tutorial on the link above talks more specifically on things I do.
2) Advertising Feedbacl loop on Facebook and Adwords
http://www.decisionstats.com/2009/05/18/advertising-feed-back-loop-facebook-and-adwords/
A compare and contract on using the very intutive feedbacl loop ( systems) for bettering your ad spend on advertising platforms.
3) Buddypress for Analytical Buddies
http://www.decisionstats.com/2009/05/12/buddypress-for-analytical-buddies/
This is a new software, a generational leap from wiki based communities. If you have a community you should atleast demo it, note it is created by the same people who made WordPress for blogs.
4) Tweets, Viruses and Bubbles.
http://www.decisionstats.com/2009/04/05/tweets-viruses-and-bubbles/
This article was written as early as 5 April 2009, pointing that ul-s on Twitter could be used for viruses, and there seemed to be a twitter application bubble. One of the earliest early warning signals on Twitter- unfortunately most of it came true in the following months.
5) Web Application aggregator
http://www.decisionstats.com/2009/04/10/web-application-aggregator-go-to-web-20/
If you like to keep on making your communications better using latest internet applications, here is a great tool
It is basically the Craigs List of all internet utilities, add-ons and applications from http://www.go2web20.net/