It is obvious that the 2 books focus on different areas.
J2EE big picture focuses on high level detail for each J2EE components. It maybe used by people who may have less experiences on J2EE, such as top management, or newbie.
The Expert-to-Expert book, as its name implies, it focus on expert developers to solve development problems.
Thus, it is difficult to compare apples and oranges.
Nick
SCJP 1.2, OCP 9i DBA, SCWCD 1.3, SCJP 1.4 (SAI), SCJD 1.4, SCWCD 1.4 (Beta), ICED (IBM 287, IBM 484, IBM 486), SCMAD 1.0 (Beta), SCBCD 1.3, ICSD (IBM 288), ICDBA (IBM 700, IBM 701), SCDJWS, ICSD (IBM 348), OCP 10g DBA (Beta), SCJP 5.0 (Beta), SCJA 1.0 (Beta), MCP(70-270), SCBCD 5.0 (Beta), SCJP 6.0, SCEA for JEE5 (in progress)