Just to kick in my $0.02, I'm currently working on something quite similar, ie. an XML resume which can be used to generate various formats. I'm using XML::Simple to parse my XML, followed by Template Toolkit to render my resume in plain text, HTML, and LaTeX (for PDF and PS creation). So far, I'm quite pleased with the results; if you come across issues of abstracting your document layouts, I highly recommend checking out Template Toolkit.