New: code-folding closures for Java, Javascript debugger via Firefox plugin, PHP support, Flex/AIR development, Android, Google App Engine, GWT 1.6, Improved Grails, Issue-tracker linked Task Management, Tapestry, OSGi development, and more. - Ray Cromwell

The world's best IDE just got better (sorry eclipse fans :) ). - Ray Cromwell

I like Eclipse, personally - hopefully they can get their photocopiers warmed up quickly, though ;) - Matt M (inactive)

I could never get used to the somewhat inconsistent UI in Eclipse that I think arises from the 'everything is a plugin' design. With IDEA, yes, there are plugins, but generally, everything is so tightly integrated together that in general, it's a true multi-language context sensitive editor and lots of stuff just "works" in each language context. The Jetbrains guys are pretty amazing and they seem to really love languages. I do acknowledge that Eclipse seems 'snappier' and the background compilation stuff is nice. Plus, you've got the Google official plugin. :) - Ray Cromwell

I have to give huge props to the IntelliJ guys overall. I like Eclipse as well, perhaps because it's just what I got used to (like vi). Swing UIs drive me crazy, though. OTOH, I remember when I first met one of their executives (Alex Tkachman) when we first released GWT, and he wrote the first GWT plugin himeelf in a few weeks. Smart group of people! - Joel Webber