I explored the 4 news sharing sites, and I think I most preferred Newsvine.
Love it or hate, it pays to be in the know. I thought this was kind of a profound quote in the 23 Things tutorial.
I think Reddit, Mixx, and their counterparts have value in that they may encourage "news" reading. Anything that encourages reading is a good thing. The model of peers recommending to peers is both encouraging and, possibly, frightening. I'm not sure whether everyone is on the same page when using the word "news." Is it really news, or is it infotainment? Will the latter replace the former? Should news be reduced to little bites of information?
As you can tell, I have far more questions than I have answers. For me personally, these tools are not a productivity enhancer. I currently do not have a need to aggregate what I read and then disseminate it to others. Having said that, I am glad to have the opportunity to explore these tools since they're being used by a lot of others.