Now Eclipse -- that's ugly, inside and out.
It's a great IDE, general usability is certainly better than Eclipse (it was meant to be an IDE as opposed to Eclipse which is a platform with an IDE built on top), but personally, font rendering was a deal break.
Their icons are, well, tasteless is the best way to describe them.
I know people don't often talk about usability and developer tools - but it really really matters. You spend a LOT of time on it - may as well fuss over it and make it right. IDEA gets so much right.... and this is also a good example of when user experience can be great, but design (graphic) not so great.