I hate to change emphasis from 1.4 to 2.0 in the middle of a series of articles, but the UML 2.0 Draft Specification is an important step forward, and I feel the need to spread the word.
Geronimo isn't even a 1.0 final release yet and there is already an excellent collection of documentation, articles, and draft books available from the Apache Geronimo documentation project.
They target the most influential academics to act as authors, draft the articles, and ensure that these include clearly-defined branding messages and appear in the most prestigious journals.