I really like the way he limits his list to 4 books. Most other thought leaders/influencers/CEOs do lists of 10, 20 "hot topic" books that you know they probably haven't read. I find the volume also diminishes the individual importance of each book on the list. I'll have to pick up String Theory (I love that Bill Gates reads DFW) and The Grid per his recommendations.
I've been doing this when friends ask for recommendations to cities. Google and guidebooks are already at their disposal, so a manageable list of 3-5 options with some personal insight is better than a comprehensive, but impersonal list of 20.
And if folks haven't read DFW's Roger Federer as Religious Experience in String Theory, you can read it on the Times web site (but you should also look into reading the rest of his works):
http://www.nytimes.com/2006/08/20/sports/playmagazine/20fede...