What is the Visual Studio shell (standalone shell) good for?

Question

Is it some sort of pre-built GUI scaffolding?
Why would I Want it instead of a WinForms UI, which is quick to set up?
What does it give me that I would have to spend

Answer 1

I used the integrated shell to try IronPython at home, without having to install the full VisualStudio trial version. It's a nice IDE if you're used to it.

It seems there is a big difference between the integrated shell and the isolated one.

The integrated shell is an IDE without any programming language installed. If you don't have VisualStudio but want to use a free plugin such as Python Tools for Visual Studio, then you can use the integrated shell.

The isolated shell is well described in Powerlord's answer, it seems to be made for programming software developpers, since it allows branding and modifications of the user interface.