You could decide to transform the user blurb/article to conforming XHTML. For "entering" HTML, I would give the (non-technical) users some editor that ensures well-formedness, like fckEdit. Then you can just check that all tags are either paired or in a list of known unpaired tags.

In reply to Re: User Input for Web Content by Corion
in thread User Input for Web Content by John M. Dlugosz

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
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