Some websites similar to Digg are:
1. Stumble Upon: Really beautiful website, and as good as Digg. Also, it has su.pr website which directly shares a Link to your Facebook and Twitter account.
2. Reddit: I think Reddit is the biggest social bookmarking website. It is really famous, and the design of the website is simple (but looks old). Once a link gets plus votes, it will start to get more views.
3. Pinterest: Particularly, image sharing, but using Images you can share the links.
4. BuzzFeed: Another easy link sharing website. Has a Page Rank of 8 and Alexa rank of 620.
Also, work on Keywords to improve the rank of your hubs in search engines. Keywords are important factors that effect the page-views.