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 time writing?
Do I get floating windows and docking, like in Visual Studio 2008?
Is there a money-cost to using it?
What does the deployment look like - is my app a standalone EXE, or is it shipped as some sort of one-off package or archive that runs within the shell?
Is Eclipse RCP a good comparable, and if so, how do they compare?