I wrote about this back in May but wanted to remind you about the navigation links in adCenter, in case some of you may not know they're there. These are horizontal links right underneath the Microsoft adCenter logo on the top left-hand side of the UI.
When you're moving around in your campaigns, you can click the green arrow next to the ad group or campaign in the horizontal navigation list, and additional navigation links will appear in a drop-down list. You can then navigate within the hierarchy. This way you can click directly to the ad group or campaign you want to review or edit without extra clicks:
Ad groups
Campaigns
I hope this helps those of you who may not have noticed this feature.