Is XML just for Programmers?

No.  XML is making its way into all kinds of Internet technologies, 
including HTML.  Microsoft is leading the way in incorporating 
XML into its browser.  Starting with Microsoft Internet Explorer 
4.0, you can create XML data islands within your HTML that can 
be used to dynamically update data within the document instead of 
having to retrieve it from the server.  It also incorporated XML 
support inside of the Document Object Model (DOM), making it 
easy to request XML documents from the server without having to 
constantly refresh your HTML pages.

It is expected that both Netscape Navigator and Internet Explorer 
are going to increase their support for XML as new versions of their 
respective browsers become available.  Before long, XML will be as 
common to Web content providers and authors as HTML currently is.  
Since XML is truly extensible, do not be surprised to see XML 
versions of HTML documents supported in the future.

XML is becoming the standard for all kinds of data storage.  New 
word processors and spreadsheets are outputting their data in XML, 
making it much easier to import and export data between platforms 
and applications.  

XML is not just for programmers, even though most users will never 
directly interact with it.  It is a world wide standard that makes data 
storage and transfer much easier and reliable than ever before.