Should Books be classified?

When planning to write a book, one of the decisions you have to make is the depth of language and how graphical your descriptions will be.

There are books these days with almost every page lined with swear words and sex references. The theme clearly not meant for young people.

Should there be age classifications (very much like home videos) for books especially novels? And should publishers be compelled to indicate this on book covers?

I think this subject is very much open to debate, but yet it may be unfair to stigmatise books in this fashion.

With the recent withdrawal of Twilight books from the shelves of Deseret bookshops (http://bolalawal.blogspot.com/2009/04/deseret-bookshops-removed-stephanie.html), one wonders why bookshops reclassify books. May be if classifications were more obvious in the first instance, a lot of this surprises will be curtailed.

On the other hand, religious bookshops, Governments and local libraries will argue on their rights to refuse or to reclassify to display particular books.

What do you think about this issue? Have you had your books taken off the shelf or refused by a library or in a particular country?

Let's hear from you.