I think SO's minimal editor with markdown syntax has been remarkably effective for the purpose that it serves.

In my opinion, the less HTML you have to deal with in submitted data, the better. Unless users need to organize and post data in tables or something, I really don't see the need for a WYSIWYG editor.

The common tags that you'll want to allow are:

<a>
<blockquote>
<pre>
<b>
<i>
<sup>
<sub>
<ul>
<ol>
<li>
<br>
<img>

Paragraph formatting is easily done on your side. With the exception of a few, markdown or creole can handle pretty much all of that, and validation / sanitation isn't as cumbersome on your end. BBCode is also fine, but not as flexible.

Unless the user is authenticated / trusted somehow, you probably don't want them having at a WYSIWYG editor.

I think SO's minimal editor with markdown syntax has been remarkably effective for the purpose that it serves.

In my opinion, the less HTML you have to deal with in submitted data, the better. Unless users need to organize and post data in tables or something, I really don't see the need for a WYSIWYG editor.

The common tags that you'll want to allow are:

<a>
<blockquote>
<pre>
<b>
<i>
<sup>
<sub>
<ul>
<ol>
<li>
<br>
<img>

Paragraph formatting is easily done on your side. With the exception of a few, markdown or creole can handle pretty much all of that, and validation / sanitation isn't as cumbersome on your end. BBCode is also fine, but not as flexible.

Unless the user is authenticated / trusted somehow, you probably don't want them having at a WYSIWYG editor. Even then, they should be really trusted, beyond just verifying their e-mail or something else that can be trivially accomplished.