update time. Both Visio & OmniGraffle w/ sitemap are good solutions. In the end, the client found that those applications by themselves produced too much granular information to be useful. For example, if a site has 30 product pages, each with their own overview, specifications, and documents sections the tree gets very big indeed. I solved for this by taking the sitemap and scrubbing it in Excel first to eliminate redundancies, and then generating the sitemap. A bit time-consuming but worth it in the end.
Thanks!