No, I don't. But at least it gives me some extra revenue without having to do a lot for it. Just writing content and hoping my visitors like it and have time to share it But I see your point
The biggest problems with Digg and other sites like it is the initial impact is short lived. Building good quality links in solid niche' or general based directories can offer a long term consistent flow of traffic.
agreed. this touches on a very important point for submitting to (good/quality) directories, not only as pointed out does this help the SEs determine what your site/pages are all about but it also helps give more Trust and Authority to your domain/website , and Trust and Authority (T & A) are now among the most important factors in determining serps. a listing in valuable directories like yahoo, dmoz, botw, joeant, goguides, aviva, greenstalk, etc etc adds T & A and that's a lot more important, in general now, from what i read than the raw pagerank juice they might give you, though that too can be important. so stop chasing pagerank so much and start going after this in your directory submissions etc....and it's perhaps doubly good by submitting to directories that are already listed in yahoo &/or dmoz