?winner ? ?winner + ?2winner/c * v((?winner-?loser)/c,?/c)
?loser ? ?loser - ?2loser/c * v((?winner-?loser)/c,?/c)
?2winner ? ?2winner*[1-?2winner/c2 * w((?winner-?loser)/c,?/c)]
?2loser ? ?2loser*[1-?2loser/c2 * w((?winner-?loser)/c,?/c)]
c2 = 2?2 + ?2winner + ?2loser

That's XBox Live's new TruSkill ranking system. Make no sense? Yeah neither to me :P But it's copyrighted and supposed to change the face of how we game, (or get own by pimply faced 14 year olds) forever!