henry0 - 6:03 pm on Apr 6, 2012 (gmt 0)
I am saying it since a long time, be careful with your followers, review their "about".
Follow only accounts that could benefit you, number is worthless, look for quality in a similar mode you will look for getting or accepting links.
lexipixel mentions to check what they tweet about, this is a great advice; for example I often tweet about fresh added content that I know is in the alley of my followers, within 15 minutes I got many retweets.
Quality is again what maters!