Geometric discrepancy (An illustrated guide) by Jiri Matousek

Some striking new developments in combinatorial discrepancy in 2010-11

A revised second printing is out (January 2010)

with known errors fixed, references updates, and with a short appendix describing new developments. The appendix plus the updated bibliography can be found here.

Errata for the second printing (2010)

Errata for the first printing (1999)