Look at IntellijIDEA IDE, its a pretty sick ide but its made in Java and we all know that Java suck at GUI. Same goes for Eclipse. Though its way better and adopted SWT but it could have been best if it was developed in C/C++. We have really good systems now and thats why we don't feel that these IDES are nothing much but a memory hog.

Why the IDE's have to be written in the language they are designed for ? Okay i know that IDE is a cool way to show how strong a language can be but even then someitmes, that specific language might not be best for a particular tastk.