The Applet features I appreciate the most (probably all):
- Applet startup time with the quick starter is blazing fast and doesn't slow down the browser
- Applets run in their own JVM process and can be isolated to one JVM per applet (finally you can provide your applets with a sane VM and you can kill offending applets without killing your browser)
- Support for JNLP (native libraries / custom JVM startup parameters like memory settings, hallelujah)
- Customization of JVM launch feedback, no intrusive Sun logo if you want a clean integration (this was a personal request, thanks a lot!)
- Improved Java - JavaScript communication (I foresee a bunch of Applet widgets :)
Damn, this should have been applets way back in time, but now I truly believe the war for the next gen web platform is on! And again congrats Java 6 update N team, you guys did a hell of job!