Perhaps I'm biased as I run several Ruby sites but
http://www.rubyflow.com/ is probably the closest to what you want. It's a community driven Ruby and Rails link site. Anyone can post there but I "curate" it (delete spam, edit descriptions if they're weird).
I also run http://rubyweekly.com/ which is a weekly Ruby e-mail newsletter.
I'm also co-host of http://rubyshow.com/ which is a weekly Ruby news podcast (and covers much the same stuff as the newsletter). There's also http://ruby5.envylabs.com/ (which I'm not involved with) if you prefer shorter and sweet news coverage in podcast form.
http://planetrubyonrails.com/ is a cool "planet" site if you want a roundup of blog posts though it's not as up to date with sources as it used to be but is the best planet site nonetheless. http://rubycorner.com/ has more links but doesn't show the items inline.
Last but not least, http://reddit.com/r/ruby is a Ruby subreddit and has a reasonable selection of stuff. Including, often, stuff not on the other sites (but the same goes the other way too, of course).
