Comment 2 for bug 863866

terminators primary method to open urls is "gtk.show_uri" which is available since PyGTK 2.14 and now depends on mime-types, not on gconf-settings.

You have to add something like this to your ~/.local/share/applications/defaults.list

[Default Applications]
x-scheme-handler/http=chrome.desktop

if gtk.show_uri is not available or the pygtk version is too old, terminator falls back to xdg-open. If xdg-open fails for any reason it falls back to "webbrowser.open" which uses the BROWSER environment variable.