I can get traffic from these guys, but they don't get me any clicks. To me, this traffic is worthless. Anyone ever get clicks from these quick traffic sites?
Most of my traffic comes from digg. I get little clicks from them, I just use most social bookmarking for exposure.
It most likely depends on what you're doing. Exposure is a good plan. Of course, if your site isn't unique, updated and interesting, exposure doesn't mean a hell of a lot.
Also Digg (reddit and other social bookmark users) users are internet trolls. They don't like advertisements.
No, these users don't click on ads much. However traffic is not useless. A lot of traffic will improve your Alexa score and you will get paid better from TLA or services like that
Traffic from digg and social bookmarking networks won't bring in any revenue, but great for gaining backlinks.