Flock

The Flock browser is based on Firefox and it still in beta -- but it has some very interesting capabilities:

• Manipulating photos for blogs or personal spaces (MySpace, FaceBook) is much easier
• Search provides results as you type and from multiple sources
• Subscribing to RSS feeds can be a one-click function
• Blogging into a specific service can be done via Flock
• Creating Favorites is easy and can automatically feed into your social bookmarks service

It's not all there yet. Their release notes state that you cannot:

• View your favorites by tag
• Upload photos directly from a camera in Windows
• Use Flock via a proxy server
• Export Favorites to a file
• Import Favorites from anywhere but Firefox the first time

If you are OK with these limitations, which I assume will be dealt with in future releases, this looks like a great browser to try!