Eclipse and NetBeans, and also IntelliJ IDEA, are all very good and professional-quality IDEs. One is not clearly better than the other; which one you use largely comes down to personal preference.
I've worked on projects where we were all required to use the same IDE, and other projects where the developers all chose their own IDE (and it was their own responsibility to make sure they could work effectively with it).
There's no clear answer to the question of which IDE you should learn to use first.
Chinna Eranna wrote:I prefer eclipse, as it has vast community support, numerous plugins, support for different languages, etc.
NetBeans and IntelliJ IDEA also both have vast community support, numerous plugins and support for different programming languages.
Agree with Jesper, its a personal choice. Its good to be familiar with the popular ones mentioned by Jesper. Few oraganisations may use Eclipse but few others might use Netbeans and few others IntelliJ IDEA (and few JDeveloper?)
John Gref wrote:I and Oracle prefer NetBeans because it is user friendly IDE i believe.
Oracle supports a lot of IDEs. Primary one is JDeveloper, their own breed. They develop components for business development for Eclipse. And they got Netbeans (more or less), when they acquired Sun, and seem to continue supporting it.