I agree, the information is dated. It's the little mini-essays celebrating the philosophy of thrift, frugal living, and wise money management that are timeless -- and delightfully well written.
It's curious to track these same ideas as they keep percolating up through the excess. And not only the ancients of a hundred or a thousand years ago. Charles Long, Ernie Zelinski, and the "Your Money Or Your Life" folks. And
online, Pete Adeney (a.k.a. MrMoneyMustache.com) et al.
Actually, it would be cool to see/hear Paul Wheaton and Pete Adeney shooting the sh-- and comparing notes over a couple of top-shelf pints. There is so much crossover it's insane, and yet their approaches are completely different. And they're both software engineers, hacking The System. Hmmm...