1) reddit - here, you have to subscribe to the right mix of subreddits according to your interests
2) Google+ - also quite good, but one needs to do some work, namely to find the right communities, pages and people to follow.
But if you are asking about sites with the same "genre" as HN (the same functionality), then no, I haven't found alternative to HN.
could you link? I subscribed to some lang/framework/os ones, but didn't find much value there and found it's better to follow people. if you got some it would be nice.
Can you recommend some subreddits beside /r/programming and the subreddits mentioned in the sidebar of /r/programming)? I have not found a generic software engineering subreddit (probably without any web development content), which is quite strange.
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