Darren Neimke, Mr. RegEx himself, has written a cool article that shows you how to create a fairly generic markup system to turn text into marked up HTML based on keyword information stored in XML... cool stuff;

http://msdn.microsoft.com/vbasic/default.aspx?pull=/library/en-us/dv_vstechart/html/vbmarkup.asp

Surf on over and let him know what you thought of it!