Hmmmm... I would never call myself a 'news' person. Do I watch it if it's on? Well, until they give the weather forecast. Or if they're making something delicious or talking about spring fashions I'll tune in. To be honest, news tends to be a bit repetitive and dull to me. You can only watch them report on the same things OVER and OVER again for so long.
However, what I really like about Digg and other social media sites is that they have a HUGE variety of articles, and a lot of them are ones that aren't seen on other sites. They're the most popular, the oddest, the ones that more reputable sites may simply 'pass' over. When looking at them, I was struck by the massive variety of subjects that were covered. Everything from the humorous to the serious was a click away. Because of the variety, I could see myself glancing at it from time to time for a look at what is going on in the world. Not only that, but because a person can recommend/share/etc an article, the reader has an idea of how many other people have read it and found it helpful. I also LOVE the idea that if I read an article and love it, I can post it to Facebook for my friends to see.
I'm not sure how helpful a site like this would be for a library. While they are entertaining, I for one ran across a few articles that seemed a bit 'R' rated. While for me, I simply blushed and clicked back (Miss Sticky, what are you looking at!), the adult nature makes it less than friendly for a library environment. We cannot police what goes onto these sorts of sites, and if we endorse them openly, there is a chance that children could run across inappropriate articles. So, while I personally think these sites are a fun and fascinating look at internet/news/pop culture, I am less than eager to recommend its use in a professional environment.