[PageRank]

   Here we're going to learn about the

CheiRank

  "The CheiRank is an eigenvector with a maximal real eigenvalue of the Google matrix G * constructed for a directed network with the inverted directions of links. It is similar to the PageRank vector, which ranks the network nodes in average proportionally to a number of incoming links being the maximal eigenvector of the Google matrix G with a given initial direction of links. Due to inversion of link directions the CheiRank ranks the network nodes in average proportionally to a number of outgoing links. Since each node belongs both to CheiRank and PageRank vectors the ranking of information flow on a directed network becomes two-dimensional." (From Wikipedia)
 
 More about CheiRank's definition, images and examples you can find following this link: http://en.wikipedia.org/wiki/CheiRank

[SEO]

 CheiRank is as important as the PageRank, I think, but it's not so popular even in the netizens among the SEO world.
 This is a good article:

Google matrix of the world trade network
by L.Ermann and D.L.Shepelyansky
arXiv:1103.5027
http://www.quantware.ups-tlse.fr/QWLIB/tradecheirank/

[Gay]

 That's right.

[swaggy]

To be honest this is the first time that I heard about CheiRank and how important it is on SEO world.