Python Tools is basically just like using VS but with Python. It's got intellisense, debugging, profiling, etc... When working w/ IronPython the .NET debugger is a little rough (you'll see internal implementation details) but you can still use the pure Python debugger which gives you a Pythonic view.
The intellisense engine is aware of the GUI designer so you'll get completions against the controls defined in XAML. And you'll get auto-definition of handler methods when you do things like double click on buttons in the GUI designer or select to define an event handler in the properties pane. Probably the biggest missing thing is that there's no support for user controls and there's also no designer support for WinForms.
