Dave Jaquay is leaving the .NET world and returning to Java. He sees C# and Java as comparable languages (giving the edge to C#) but is excited about switching Visual Studio for Eclipse. It's an interesting read. I'm doing some Java work now and using Eclipse. A few things I very much agree with Dave about (rebuild-on-save, JUnit unit-testing integration). Maybe it's just that my fingers know the VS keybindings better, but I still prefer VS to Eclipse.

I have to say that Eclipse is a heck of a platform, though.