I\'m planing to buy a Mac. I would like to be able to develop GUI applications for Mac as well. Currently I develop in C# using VisualStudio as IDE. I also know Java and I\'
It's Objective-C. But if you want a beautiful and easy language, you can use python with wxPython. It'll look as native and, furthermore, it will make your applications multi-platform.
For the GUI designer, check wxFormBuilder. It supports wxPython for exporting.