Intellij Idea
Today Intellij announced that they are open sourcing the IDE. As usual this was a huge step for JetBrains and was welcomed very well in the development community. I am a huge fan of IDEA and have been using this for almost 5 years now. Its worth every penny in my opinion. I am interested to see where this will end up in the future. One good thing is Jetbrains is still continuing a commercial version and hence the good stuff will keep coming. Now I can afford to download a free version and enjoy the same benefits.
Sorry Eclipse users you will be left behind in my opinion :-).