While trying to use the Navigate To feature (by pressing Ctrl+, or Edit -> Navigate To),
As I type in a class name, the UI is frozen for a second while the IDE opens up the top suggestion in a preview pane.
Keyboard entry still works while the UI is frozen, because after the preview pane has opened, any text entered while it was frozen appears.
I prefer this method of navigating code as it's hands off mouse. It would be nice if loading the preview didn't effect the navigate to input box or list of suggestions. Or if the opening of a file in a preview pane was significantly faster, but I guess we're working within the constraints of VS here.