Agile Ajax: More on site-specific browsers: Webkit-based Fluid

After my recent post on Prism, the Mozilla-based site-specific browsing tool, a commenter pointed me toward Fluid, Prism's Webkit-based cousin. After giving it a test drive, I'm impressed. Although it lacks the cross-platform appeal of Prism, Fluid already offers a nicer user experience than the project that inspired it.

Fluid's advantages:

Better preferences: Fluid offers a far more polished UI, including preferences that help Fluid integrate with Apple's Spaces multi-desktop environment.
Tabbed browsing: You can set Fluid up to launch secondary windows in a new tab instead of a new window. This greatly enhances the user experience of webapps with lots of popup windows. It also allows users to more easily open multiple screens of an application at the same time.
Browse any URL: Prism spawns any URL that's not part of the associated webapp in your default browser. So does Fluid, at least by default. But by changing your preferences for any individual Fluid instance, you can enable browsing to other URLs within that Fluid instance. Want to click on an outside link in a Gmail message? Now it won't take you out of context and into another application.
Less wonky Dock behavior: In the current version of Prism, when you create a new site-specific instance, Prism restarts the Dock and launches the application. Even then, the icon for the newly created instance remains the default Prism icon until you quit and restart that instance. Only then does the icon you picked - the site's favicon or any arbitrary image - show up in the Dock. With Fluid, upon creation of a new instance, you get a dialog that lets you choose whether to launch your webapp immediately. If you do, it's got the correct icon from the get-go.

Fluid's disadvantages:

Lack of cross-platform access: It's available only for OS X 10.5 Leopard, so Windows, Linux and even OS X 10.4 Tiger users are out of luck. That's the only big disadvantage I can see, but it's a doozy. Still, by providing a native Cocoa alternative to Prism, Fluid helps raise the stakes in the realm of site-specific browsing. It'll be interesting to see how this category evolves.

Suggested improvements for both Fluid and Prism:

The ability to recover from connectivity issues: If I boot up either program before I've achieved a wi-fi connection, it fails to load the associated webapp. The familiar keystroke of Command-R does nothing to reload the app once I'm online. The only way to connect is to quit the app and restart it. This is a minor annoyance, but it's especially frustrating in environments with intermittent connectivity.
A forum to post nicer-looking application icons: I'm sure that if site-specific browsing takes off, somebody will standardize a way for sites to serve a range of high-resolution icons for use by host operating systems. In the meantime, pretty much every favicon I've seen has looked terrible blown up to 4x is normal size and plunked into the Dock. As a stopgap measure, it would be great if the Fluid and Prism sites offered forums for users to post icons they've taken the time to spiff up for popular webapps.