The Go people really have figured everything out. You don't need IDEs! You need reusable pieces of code that you can plug into every other text editor, IDE or what have you.

For C/C++/Obj-C we can use llvm/clang. [1] I've found Pysmell[2] and Rope[3], for Python. C# has NRefactory[4], which is used by the Sharpdevelop and Xamarin folks. When doing java you can kind of do this with Eclim[5]. It can run a headless eclipse.

The day vim does all of these out of the box, will be a happy day!

[1] https://github.com/Rip-Rip/clang_complete

[2] https://code.google.com/p/pysmell/

[3] http://rope.sourceforge.net/

[4] https://github.com/icsharpcode/NRefactory

[5] http://eclim.org