Simply described as: Tag Mirror: What LibraryThing thinks eoinpurcell is interested in this is a pretty impressive feature and one that is of enormous use to just about everyone from publishers to readers.
Check out my Tag Mirror here
There is much more in Tim’s blog post here:
Tag Mirror “holds a mirror” up to your books and to you. Instead of showing what you think about your books—what a regular tag cloud shows—it shows you what others think of them, in effect using LibraryThing’s twenty-two million tags to organize and surface interesting topics from within your own collection.** As with other tag clouds, size equals importance. When you click on a tag, you get a relevancy-ranked list of books tagged that way.