Camino uses mac interface widgets for drop down menus and list boxes in web pages. It also doesn't support firefox extensions.
It does have its own ad-blocking that works pretty well.
Here's a quote about the mac-specific features:
"
Dedicated Integration
Camino integrates tightly with your Mac OS X computing environment. The native Cocoa interface and the beautifully-designed icons make Camino a very useful and elegant desktop citizen.
OS X Integration
But integration does not stop with Camino's appearance. Camino incorporates features that use Spotlight, Address Book, the Keychain, the Finder, the Dock, Bonjour, Services, and System Preferences. The Camino Project's commitment to the platform shows in its support for Mac OS X versions 10.2, 10.3, and 10.4; on each version, Camino provides the seamless experience users have come to expect from software running on Apple’s Mac OS X."
