Eclipse has always seemed to me to be baroque and over complicated, for example why do I need to change to a specific perspective to perform a specific task?
http://roboprogs.com/devel/2009.09.html
The vim (key assignment) editor NB plugin is kind of useful as well.
Like Tim said, Eclipse is overly and needlessly complicated.
As for IntelliJ, never bothered to try. It seems to have a very passionate user base, but, from what I saw, I don't know why.
http://youtrack.jetbrains.net/issue/WI-2457?projectKey=WI...
That's one reason for me to keep using Netbeans, which I think is great for PHP.
The same can be said for eclipse and I think there was a time when the eclipse framework was just so much "snappier" due to SWT that people forgot all about netbeans... but with more recent JDKs and more recent versions of netbeans, this isn't necessarily the case anymore.
IntelliJ has always seemed incredibly neat and those guys are doing a great job considering they are up against giants like sunoracle and IBM - personally the only thing that ultimately kept me from using intellij more at work was the price but I see they are offering personal licenses at a more reasonable price now so it is definitely a viable alternative to look at and try for devs.