Here's how you can get a sweet Visual Studio development experience for building and debugging your own PowerShell cmdlet:- It has Wizard support for initially creating the cmdlet, - intellisense- F5 build support which also registers your cmdlet- provides the full power of the VS debugger including Edit-and-Continue when debugging your cmdlets.
David Aikens has a great tutorial for how to build a Power Shell cmdlet in the VS ide. This does 99% of the work. He's got great wizards that makes things very easy to start. His tutorial describes the rest of the steps that need to be done manually. Conveniently, all of these steps can be automated. I'm assuming there's already some sample VS project in the Power Shell SDK or somewhere that does that; but if you want to create such a project by hand, here's how...
Now you can develop your cmdlet in the IDE as you'd expect, complete with intellisense. When you Build in the IDE, it will automatically run installutil and install your cmdlet. When you F5, it will launch PowerShell under the debugger, and load your snap-in. Thus you can use the full power of the Visual Studio debugger on your cmdlet. When you execute your cmdlet, you'll hit breakpoints, etc.
You can even use edit-and-continue on your cmdlet. (Unfortunately, EnC doesn't support adding public properties, so you can't add new properties to your cmdlet).
You can also enable Just-my-code which will treat your cmdlet as user-code and Power Shell as non-user code and make it easier to focus on debugging just your cmdlet without debugging Power Shell.