Autodesk released the Prospector Hotfix on Sept 7, 2011.
More Than a Little Thing
I've been running a version of this Hotfix for More than a month.
This hotfix absolutely and positively saved me lots of frustration in AutoCAD Civil 3D 2012.
If you want to edit any large collections of anything in the Prospector AND particularly over in the Settings tab, Civil 3D 2012 can be very problematic without it.
Imagine working on 5000+ Styles in the Jump 4 Civil 3D 2012 day after day without it. Nah. Don't do that. It will make you crazy...
I think they should have called this the "Toolspace Hotfix" but who am I to talk about naming anything anyway?:)
A very special thanks to the civil development team for letting me have and test this early.
Things do get better - sometimes only one little thing at a time.