Any good survey of thought in any discipline or of any particular period ought to meet a few critieria to be highly useful.
1. It must be representative.
2. It must be more descriptive rather than judgmental in its exposition.
2. It must be informative.
3. It must be concise.
5. It must be lucid.
6. It must set the expectation right.
This survey of contemporary thought meets 4 of these 6 criterion. However it fails to be representative, which I believe is the most important chracteristic of a survey of thought. It also sets the expectation wrong with the phrase 'Fifty Key Contemporary Thinkers'. It fails to be representative in the following few ways:
A. Most thinkers are French.
B. Most thinkers are those who rose to prominence in 1970s and were on wane in the 1990s.
C. Most thinkers are from philosophy.
D. Some thinkers celebrated here have hardly any widespread influence on contemporary thought like Canguillhem, Cavailles, Pateman, LeDeouff et al. Nor are these thinkers originators of any breakthrough ideas.
E. Some thinkers who have had a major influence on contemporary thought like Giddens, Elias and Luhmann in sociology, Alisdair MacIntyre et al. in philosophy, have not been represented.
6. Written about ten years ago, it is already a little dated with new thinkers like Alain Badiou, Richard Rorty, Daniel Dennett, Roberto Magngabeira Unger, David Chalmers, Michael Walzer, George Sher, Antonio Negri et al., who rose to international proimenence in social sciences/philosophy in the 1990s, not being covered.
7. Scientists will hate this book. It makes it seem as if thought is only social science.
That stated, there are also significant merits of this work which makes it worth reading.
1. I had not heard about influential thinkers like Deleuze/Guattari, Lyotard and others before reading this book.
2. This book gives a very good, concise and lucid overview of the thought of the thinkers selected (irrespective of the bias) in the tradition of Diane Collinson's work (which provided the model for this).
3. The trends covered here are certainly the more dominant or controversial trends rising to prominence in recent decades (in social sciences, especially philosophy).
4. Many (but not all) of the trends/thinkers covered have had a cross-domain influence, although they originated in philosophy.
Perhaps this book would have been more satisfactory if it had been titiled right, maybe Fifty Key French Post-Modern and Miscellaneous Thinkers. With its current title, this book has the bias of leading the reader towards developing an interest in post-modern thinkers. If taken as a reference bible it would opens reader's minds to new thought but end up closing their minds with post-modern rantings.
For a good survey of thought, the readers may also consult some of my favourite sources for catching up with information important thinkers (in areas as indicated in brackets):
1. Thinkers of the Twentieth Century (all subjects till from 1900 to 1970s/1980s)
2. Dagobert Runes' Pictorial History of Philosophy (for philosophy -- ancient to 1950s)
3. Frank Magill's Masterpieces in World Philosophy (for philosophy -- ancient to 1950s)
4. William Ebenstein's Great Political Thinkers (for political thought -- ancient to 1950s)
5. 18-volume International Encyclopedia of Social Sciences and Biographical Supplement (for social sciences - late nineteenth and first half of twentieth century)
6. Charles Coulston Gillespie's Biographical Encyclopedia of Scientists (for science - not sure this is the exact title).
7. Lewis Haney's History of Economic Thought (for economics, somewhat dated - covers economics till the Keynesian revolution only)
8. Other volumes in the Routledge Key Series (much better written).
9. Ross Stagner's A History of Psychological Theories (for psychology -- ancient to 1960s)
10. Robert Gorman's Biographical Dictionary of Marxism and Biographical Dictionary of Neo-Marxism (for Marxism - the Marxism dictionary has a lot of trivial thinkers of very minor consequence making it seem a laundry list; the Neo-Marxism diciotnary is somewhat better.)
11. Tom Bottomore's Dictionary of Marxist Thought (for Marxism)
12. Elmer Borklund's Contemporary Literary Critics (twentieth century literary critics).
Many of these works except Routledge Key Series are out-of-print although not completely dated, and anyone who gets hold of a copy will find a lot to explore in the areas these books pertain to. For other specific subject areas, I have not been able to find good biographical dictionaries or subject histories, although I tried, and had to pick up references the hard way, through citations and book indexes.