Although I got the answer right, it's kind of misleading... if the value of a column has been updated to the same value (usually do to bad GUI code), do you want, say, an audit trigger to still fire? It will if you only use the correct answer... if you don't want it to, you must also compare the values from the two trigger tables, taking null into consideration, to see if the value actually changed.
--Jeff Moden
Change is inevitable... Change for the better is not.