Originally Posted by topEG

I think forum signature makes sense more than social bookmark or social network.

However, some social network has more power to major search engines such as digg bookmark will be usually crawled, cached and indexed within 30 minutes by Google.

It is wonderful web traffic you will get from the powerful social bookmark, but don't spam it. Please do it naturally in order to keep it as a reliable social network in the eye of major search engines.