Mustang, the latest JDK (to be called Java6 on its release), fixes a minor but very annoying nit that's bugged Java developers for years: "if a JDBC driver is packaged as a service, you can simply (leave out the call to Class.forName() to bootstrap the driver class into the JVM). ... The DriverManager code will look for implementations of java.sql.Driver in classpath and do Class.forName() implicitly." It's never been a huge deal in Java, to have to explicitly bootstrap the JDBC driver into the JVM before being able to obtain a Connection from it, but it's always been annoying, and inexplicable, given the Service Provider mechanism that's been there for a couple of releases now.
Next up: do the same for JNDI and XML parsers (and do away with the extensions directory while we're at it!), and let's start making all of these factories a bit more practical to use on a larger basis. It would be nice if this mechanism had percolated through other tools and areas, such as servlets, but it's probably too late to correct for that now.