Programmers never get to know their tools inside out, because every large change forces them to restart part of their trek up the learning curve. Some of Java's features should improve the reusability of software pieces, and this will make it easier for programmers to improve the quality and flexibility of their products. But that won't happen until the tools stop evolving so quickly. For years we've heard talk about products users can customize by changing parts such as spell checkers and graphics editors, but that technology never materialized, largely because software companies lacked sufficient incentive. Java and ActiveX are moving in that direction, and products such as Lotus' Koa and Corel's Alta will tell us if users really want this capability.
Internet security is a scary issue.
Java applets are inherently safer than ActiveX, and unlike ActiveXcontrols, they make no changes to your system configuration. But security issues will continue to crop up for Java, ActiveX, and all operating systems and Web browsers. Still, Java will probably continue to be at least somewhat safer than average. The most malicious Java applet can't touch your harddisk or Registry. For instance, if you wanted to use a local document, the Java applet wouldn't be able to read it.