Delicious.com is one of the best social bookmarking site alongside with Digg, Furl and some others. And getting something of your interest into the top is challenging, but finding something that might interest you, is also not an easy task.
As Delicious works on tags, the sites are bookmarked with certain tags and those when searched, gives results with the most saved websites for those tags. But Delicious does not have some features that Popacular has.
Popacular is a site that lists the most bookmarked sites for a certain period of time, like the last 8 hours, last 24 hours or the past week.

Not only the last 24 hours or the past week, but the most shared websites in the last hour are also listed which can make you understand which were the most active tags and topics in the social bookmarking world during the past hour.
Popacular also shows the most shared websites on twitter, apart from Delicious, and is the website behind Gigatweet concept of twitter.

Learn about the latest trends in the web through Popacular.
Check the Popacular website at popacular.com!