I've been watching from afar the outcry over the shutting down of Google Reader. Previously a heavy gReader user, I've gradually moved away from the service, the move coinciding very much with the emergence of Twitter as an effective content curation platform. Nowadays, when I find an interesting post / blog, I usually try to find the author's Twitter account and follow it. This way I not only get updates on new blog posts in realtime, I also get additional content via regular tweets that might be of interest.
The asymmetric Twitter following model really supports this behavior - for a long time I used Twitter almost exclusively as a content curation service. While my Google Reader account was getting out of hand with the guilt inducing +1000 unread items, with Twitter I never felt pressured to chase "Inbox zero" on my read count. I might miss some good content, but in most cases if it's interesting enough it will float up again and I'll catch it anyway.
With the deprecation announcement of Google Reader, many new RSS subscription services popped up / gained popularity, and I wonder whether they're catering to an inferior content publication approach. If you look at the Google Trends chart Andrew Chen put in a recent post, the downwards trajectory correlates well to the launch of Twitter (Mar. 2006).
My 2 main sources now for new + interesting content are Twitter and HackerNews. HackerNews pushes to the top the really popular items (so it's basically my actual "news" source), while with Twitter I can personalize my stream to suite my interests and preferences by managing the people I follow. I get introduced to new content via RTs and mentions, so my content stream is always expanding.
While I think RSS failed mostly on marketing and usage penetration for the average user, I also think it had problems scaling as your subscription inventory grew. I (and probably most people) don't have time to read everything interesting that crosses our way, and in that sense Twitter has become the content subscription service I actually needed.