Twitter may be great for picking up stories that fly under the radar of mainstream news stories and trusted blogs. People, such as tech writers, who need to obtain news a little earlier may also need to follow Twitter. However for real news reading I find it a better use of time to go to primary news sources or news feeds. Lately on Twitter I've been turning up stories that, far from being cutting-edge, are just old news, no longer relevant. Other stories sometimes turn out to be baseless rumor. To filter through all the chaff takes time - the more populous the stream, the longer it takes. It's both a lazy and a tedious way to follow news. Every click takes time.
No doubt building up a large number of relatively trusted streams, then reading them through filtering mechanisms like Twitter Times, can be effective. But it's easier to accomplish a useful news stream using Feedly, for example.
It would be good if Google (or Feedly) could weight stories in one's news stream by checking all interactions with a given story, by shares, retweets, Url shortening, Diggs, etc., and also emphasize links with activity from friends across social networks. No doubt that will come, just as Google is trying out a similar feature for general search results. But even without it I think that RSS streams are the way to go, and an easier choice for obtaining a good balance of news than attempting to obtain the same from social networking services like Twitter.