I am not an Eclipse or IntelliJ user so I have no idea which is better but I have used Eclispe once a couple years back and it's UI simply sucks and doesn't catch my attention. I have forgotten the version but it seems to me Swing (Metal and recently Nimbus) actually looks quite good anyways.
I am a NetBeans user and have ever since been stuck to it like a glue. It's usually nice but once in a while irritating though. I wouldn't change from NetBeans anytime soon unless some unreasonable policy or license appears from Oracle (I'm monitoring hard on the situation).