use simple BBCode in your comments 
atm follow tags available:
[b]bold[/b] 
[i]italic[/i] 
[u]underline[/u] 
[color=color]text[/color] example [color=FF6600]Text[/color]
list 
[ul] 
[li]number 1[/li] 
[li]number 2[/li] 
[li]number 3[/li] 
[/ul]
[url=http://www.google.com]Google[/url] 
[img=http://uri.to.pic][/img] (fix picsize)
(required wp-syntax) 
[code]your code[/code], 
optional with declaration of the language 
[code lang=”csharp”]your sample code[/code] (all available languages from wp-syntax possible)
<h3>Arbitrary section</h3>
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BBComments

jianmingyong

<ul>
<li>Font Bold: [b][/b]</li>
<li>Font Italics: [i][/i]</li>
<li>Font Underline: [u][/u]</li>
<li>Font Strikethrough: [s][/s]</li>
<li>Font Size: [size=][/size]</li>
<li>Font Color: [color=][/color]</li>
<li>Font center: [center][/center]</li>
<li>Text Quote: [quote][/quote] OR [quote=][/quote]</li>
<li>URL: [url][/url] OR [url=][/url]</li>
<li>Image: [img][/img] OR [img=:][/img]</li>
<li>Un-ordered list: [ul][li][/li][/ul]</li>
<li>Ordered list: [ol][li][/li][/ol]</li>
<li>Code: [code][/code] OR [code=][/code]</li>
<li>Youtube:  OR </li>
<li>Google Video: [gvideo][/gvideo] OR [gvideo=:][/gvideo]</li>
<li>Spoiler: [spoiler][/spoiler] OR [spoiler=][/spoiler]</li>
<li>Line: [hr][/hr]</li>
<li>Sub script: [sub][/sub]</li>
<li>Super script: [sup][/sup]</li>
<li>Table: [table][tr][td][/td][/tr][/table] OR [table=][tr][td][/td][/tr][/table]</li>
<li>Hidden words: [hnote][/hnote]</li>
<li>Textarea: [textarea][/textarea] OR [textarea=:][/textarea]
</li>
</ul>

BBComments vs Extension BBcode Bata