TODO:
When deploying a feature in SharePoint 2007, Visual Studio 2008, you get the odd and vague error "Object Reference Not Set To An Instance Of An Object" error.
SOLUTION:
The solution that worked for me, was to change th "Load User Profile" to "true", in the Advanced Settings of the Cetnral Admin App Pool. Mine was set to false by default.
NOTES:
I have no idea why this works.