Gilda

The OED, like most dictionaries, is descriptive, no prescriptive. It isn't meant to describe how people should use words, but how they do. The inclusion of slang in the dictionary does not mean that its use is appropriate in most situations.

Using "ain't" is a problem not because it isn't a word, but because it's status marking slang. In other words, in a formal context, its frequent use may mark the user as uneducated.

I like the approach taken by the American Heritage Dictionary, which lists the slang terms, but clearly identifies them as slang or non-standard usage, and which has usage notes, which are boxes discussing and explaining proper usage according to a panel of language experts.

Including slang doesn't legitimize its use, it merely reflects that people are using the words in a particular way.

Gilda

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