Lets be quite clear I love Twitter, the ease of use simplicity and ablity to communicate across platforms instantly makes it a winner as far as i am concerned, BUT i still have clients who question its use and reason for being.
One of the main questions of concern i get is following people, who should i follow and why? and this i think boils down to a simple reason; that is when you follow probabaly more than a couple of dozen people your tweet feed can get full of useless chatter that makes the real message seemingly lost.
In my mind Twitter isnt about only following people who follow you — a blanket policy just wont work for those well know users, its pretty much unmanageable but I do think that it can be useful to know who follows your initial follow; To give an example, you may have followed a user back out of courtesy, but what they tweet is in your opinion low grade junk so if they have now unfollowed you, surely that gives you THE reason to unfollow them.
I use a great free tool called Twitter Karma and this shows your twitter contacts in a grid with a note beneath showing who is following whom, i use it to visually see who is doing what and within the site you can make some follow or unfollow action, you can also go more indepth if needed, try it for yourself its free.

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