I think for the latest Google updates, Off page optimization techniques also changed. Now Google is getting more response from quality links from the following resources:
Social Networking Sites,
Blogging,
Blog Marketing,
Forum Marketing,
Search Engine Submission,
Directory Submission,
Social Bookmarking,
Link Baiting,
Photo Sharing,
Video Marketing,
Business Reviews,
Local Listings,
Article Submission,
Social Shopping Network,
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