The 'web' configuration is the minimal necessary services to support a
servlet container and JPA. This configuration came as a direct result of the number of people who asked how to slim down the 'default' configuration to get it to where it would handle just WAR files. We cover this in section B.1.4
Oh, the 'standard' configuration is the one that passed the
Java EE 5 certification. We cover this in the errata (it was truly a last-minute addition).