This discussion could go on and on, and it strays from the subject at hand, but I'll just say this:
If you feel that there is too much noise in your Twitter stream, then you're following the wrong people. You have full control over who and what you follow, that's the beauty of it. I've found that in general, following any more than about 150 people will get overwhelming. Find the 150 people that are most relevant to your interests and your lifestyle and follow them.
If you're "following" 2000 people, you're actually following no one.