Sidebar design done right

I’m not usually fond of Microsoft’s UI designs, but in the case of MS Office 2003 products, they’ve outdone themselves. Look at this example of easy navigation between different sidebar options:

Microsoft PowerPoint sidebar design
Now compare this to how it looks in Firefox:

Bookmarks sidebar in Firefox

The search bar is a nice touch and somewhat redeeming feature, but having fast navigation between different sidebar options would be even better!