I searched for a bit and then took the option of joining Digg.
In order to test the search options, I chose a rather obscure subject to look for, the Bussard Fusion experiments that are ongoing. The most recent posting was from Feb.
To contrast, I went and looked for a more recent subject, Michael Jackson. The most Dugg pieces ranged from his appearence on the Simpsons to his first moonwalk.
All in all, I'd have to say that the results are somewhat "scattershot". Because this is content created by the general public, it has enormous potential. But, becaused it's content is created by the general public, it has the potential to get bogged down with inanities.