If business spamming is an issue for a twitter user then I think you are using in twitter in a wrong way. Personally, I get high signal to ration by following

If business spamming is an issue for a twitter user then I think you are using in twitter in a wrong way. Personally, I get high signal to ration by following friend(less spammy) and any new source which I am interested in. If you are getting any new source from multiple places then, it is not worth following them at all. Those news piece most probably you will get from any news aggregator. Twitter can go down the way like google news, where it aggregates the tweets/trends which matches your activity( what you follow and tweet stuff) but that should be done as alternate view. May be tweet trends will be going in that direction.