I get the bulk of my general tech news from Hacker News and Ars Technica. I track more specialized subsets on Twitter and Reddit, though the latter depends on how active the subreddit for that topic is.
I'm kind of sad about the current state of affairs. Google Reader was my primary news source before Google decided to shut it down. After that, I was an early user for a machine learning startup called Prismatic that put together a news aggregator that would take the list of people you follow on Twitter, look up the articles they tweeted, map those onto topics, and generate a news feed based on those topics. It was easily the highest signal to noise ratio of any one source I've used for news but they didn't get whatever traction they were looking for and shut the service down in a pivot before they went away.