> "Is XQuery like XSLT such that I have to build a little 
> script that will copy everything from the source to the 
> destination and make the change or add the attribute once I 
> get to it?"
> 
> In that sense the two are different aren't they...? XSLT's 
> recursive descent processing model makes it ideal for the 
> task, while in XQuery you would pretty much require XQuery 
> Update to do the same task.

Yes. XQuery tends to work better when you want to extract a small amount of
information from a large document and ignore the rest. XSLT tends to work
better if you want to keep most things the same and make a few small
changes. Of course there's a range of tasks between those extremes.

Michael Kay
http://www.saxonica.com/