Recently, I've become an avid user of the Oracle JDeveloper IDE. I must say...it rocks! I was not so easily persuaded into using the IDE though. As a matter of fact, I downright despised JDeveloper for some time...that was a HUGE mistake on my part.
When I first began Java development, I was actually using it to write stored procedures for one of my Oracle databases. I had the need to read and write external OS files from within one of my apps. There were really no great tools for PL/SQL development that offered Java code ability which matched up to what Java IDE's had to offer. I then took a look at JDeveloper and tried to use it for developing my Java stored procedures. It was a pain in the neck! I had issues trying to create a simple Java class...you need to first create a project...and so forth. The real problem was that I did not have the time or the inclination to read about how the IDE works first...I just wanted to use it. I began to develop JSP-based web applications and also tried to use JDeveloper for that. I hated the fact the the applications were structured into an Oracle proprietary format (by default), and I had to manually manipulate the format of my WAR file in order to make it work with the Sun Java Application Server. This is why I despised the IDE.
At that time, I really preferred Netbeans because it was easy to use and required virtually no "study time" in order to make great apps. I began using Netbeans back in version 3.5, and I thought that it was great. I could create a Java class easily enough, and my JSP apps were ready for deployment straight out of the IDE! I felt that Netbeans blew JDeveloper away at that time. Since then, Netbeans has really come a long way...an already great IDE has been made even better, including Java EE wizards and auto-creation of EJB3 classes in the latest beta version. I love Netbeans for it's ease of use. Netbeans is a great IDE!
Now, I just actually started using JDeveloper a couple of months ago once again because I was learning EJB3, and I saw some great JDeveloper tutorials on the Oracle site. I started to use the IDE and had the same issues once again...I was unable to deploy to Sun Java Application Server easily. I did not like that. Well, I spent a bit of time reading through some documentation, because I could clearly see that JDeveloper had some features that would make my life much easier (visual JSF development, direct deploy to OC4J...which is what my employer uses). After a bit of studying and trial-by-error using the JDeveloper IDE, I have seen it's power and have begun to use it each and every day. Especially in my role as a DBA/Developer, it comes in extra handy. I can create PL/SQL applications and database objects directly in the database using JDeveloper...no more text file development! I can also easily create a Java stored procedure and it's PL/SQL calling procedure within the IDE. I've also converted some of my JSF applications from Netbeans over to JDeveloper easily enough...and I've begun to visually create my JSF apps which cuts my development time way down. Being a DBA, I can use more time on other things than manually coding nested panels within a web page!
All in all, I want to spread the word that Netbeans is great, and JDeveloper is also excellent. I actually advocate each of them and still use them both. I use Netbeans still for any development at home. It also has a great new GUI development tool (Matisse) which makes Swing development much easier. Newbies and professionals who want to simply open an IDE and begin developing with little study time will really like Netbeans for it's ease of use. If you've got some time, I recommend that you read about and learn JDeveloper...especially if you use PL/SQL as well as Java. It will save you lots of time in the end!