I have been using Eclipse from its early days. Around 2001 i tried using WSAD on my 512MB RAM machine, and after setting WTE up the whole PC went for a toss and the slower response only increased the rate at which i was smoking. I was seeking an alternative and Gods Magical hand slowly led me towards Eclipse. I set up a very productive environment based on eclipse, tomcat (using lombaz plugin) then eventually moved on to the whole new brave world (then) of Jakarta POI etc. My open source fanatism went to the extent that when i left from Singapore (client place) to India , calls never stopped on 'How to' with what i had developed with those funky os jar files. Good old days.
The thing that i loved about eclipse was the simplicity with which you could develop things, though the EE support was a bit lacking and i had to use an array of plugins. But WebToolsPlatform completely changed this scenario with a cool support for plugging in your favorite j2ee server and toolsets. I have always had low opinions on any IDE which is non-eclipse but recently i was in for a shock when i accidentally came across NetBeans 6.5.
Though NetBeans doesn't have the community support that eclipse enjoys, feature wise it is really good, be it UML modeling, WebServices or Mobile or anything that a normal J2EE developers would use. UML modelling is one area where Eclipse really lacks or proceeding slow due to the heavyweight IBM Rational Toolkit and NetBeans scores very high on this.
While Eclipse is trying to evolve as a mother of all IDE with support for all the programming languages that exists in the world , NetBeans is proceeding with a great focus on J2EE environments, and i think a healthy competition between Netbeans and Eclipse should be encouraged to ensure the Java Lovers benefit.
All said and done, after all Sun gave us Java and i think we can show some gratitude to them by using Netbeans and making it alive to have a David vs. Goliath fight with Eclipse.