What's new in JDK 6?

According to Danny Coward's Sun Weblog there are several important enhancements:

Web Services
Easy to use APIs for developing web service clients.
Scripting
Mix scripting and Java in your code. Javascript comes as standard, you can add many more languages.
Database
Updated JDBC 4.0 APIs, and an all-Java JDBC database included in the JDK.
New Desktop APIs
Swingworker, JTable sorting and filtering, GroupLayout and more.
Monitoring and Management
All the m&m tools now attach on demand. And there's a new one: jhat.
Compiler Access
Programmatically control the javac compiler.
Pluggable Annotations
Define your own annotations and plug in the code to process them.
Desktop Deployment
Swing's better looking and better accelerated. Revamped runtime and application installation.
Security
Integration with services like PKI, Java GSS, Kerberos, and LDAP.
Performance and Quality
Double digit improvements in performance, client and server. 100,000+ tests for compatibility alone.