Continuing from Wednesday's Daypop Top 40 links theme, there is a new player on the block.
Popdex is a young new upstart concentrating purely on the 40 most popular links (Daypop's is an aside from its search engine functionality). As you would expect, some of the links listed on Popdex also appear on Daypop. Ironically I found Popdex through Daypop's Top 40 and sure enough it currently turns up in its own listing. However, the source sites are obviously different so there should be some different results.