Testing the current site
Since you've heard so much about the site maybe its time to get a little hands on with it. Spend a little time poking around the site getting a feel of its functionality and using your skills of critique. Perhaps test it in some different browsers or use Browser Cam. Pour over the usability reports, user feedback and statistic logs your client has provided. Using the log analysis tool Clicktracks you can have a visual representation of where people are going and their behaviour, using a log analyser like Webtrends or Webalizer you can get an idea of the most popular sections, files, days and times.
