47. Topic Modeling – How To Write It LDA correlates w/ Google rankings better than any other on-page feature http://www.seomoz.org/blog/content-optimization-revisiting-topic-modeling-lda-our-labs-tool
111. Incentivize Sharing in Your Community The brilliant strategy by http://www.urbanspoon.com made them one of the biggest players in the local restaurant business and got them acquired by IAC