As an anthology of history, it's a terrific look into colonialism, revolution, race relations, inflation, civil unrest and war. Great pictures, excellent annotations (lots of typos and misspellings, though not as many as in the new 1961-present volume, which may have been edited by sixth graders) and easy-to-follow chronological presentation.
As a price guide, it's still sadly lacking - there has been no serious updating of most French and British colonial values (although the values for most of the notes of France itself have been significantly increased) as well as post-WWI inflationary issues (Hungary, Poland, Germany), which all sell for considerably more than listed in the book. Just a short visit to eBay on a Sunday afternoon will dispel any notion that the price listings for these and other issues are even in the same ballpark as reality.
For the time being, it's the best thing going and well worth the price, as long as you supplement it with some online auction surfing and a couple visits to coin and currency shows, just to see what the stuff is actually selling for.