It seems like GNOME 3 is now picking the available web browsers by filtering .desktop-files that has x-scheme-handler/http;x-scheme-handler/https and uses this to display whatever is in the Preferred Applications panel in gnome-system-settings. I think that's a good thing, long term at least.

However, it is important to keep in mind that this way of doing things constitutes a _recently introduced_ 3rd party interface. Notably Google Chrome (as delivered by Google to me in RPM form via a YUM repo for my Fedora Linux OS), does not yet use this interface. As a result, it doesn't show up in the combobox.

It would be a lot easier if GNOME 3 had a "Open with other application..." as we used to have in GNOME 2 Preferred Applications and GNOME 2 Media Autorun e.g.

 http://people.freedesktop.org/~david/nautilus-autorun-stuff.png

Personally, here's how I solved the problem: First I edited /usr/local/share/applications/google-chrome.desktop (where the Chrome RPM drops a .desktop file) and then that didn't work. Ah, there's a cache! OK, then I manually had to edit /usr/local/share/applications/mimeinfo.cache because update-mime-database(1) didn't work (complained about missing packages directory). All in all, a very bad experience which I'm pretty sure 95% of non-developers would fail at.

So I'd recommend making such a "Open with other application...." feature available soon so people can type e.g. "/usr/bin/google-chrome" or whatever. Take it for what it is, but I can guarantee you that people will bitch and moan about this feature missing - I know, they did for the GNOME2 Media Autorun for _years_ even though I told them to just add x-content/* MIME types to their desktop files. Thanks.