How does "inheritance of methylation" of DNA and/or histones work? What are the current models/ideas describing the mechanisms explaining inheritance of methylation on DNA resp. histone level? Is there evidance of this "setup" information being really duplicated/inherited during a cell division process? Pointers? Articles? What is the current state of knowledge regarding this?

Jon Wilkins has a nice introduction to imprinting. He does a nice job of introducing the idea methylation and how these patterns are maintained during development and cell division. Further, he links to some interesting papers on the subject.