Can I make mailto: links open up in gmail instead of evolution?

Yes, you can use the desktop webmail application, for instance. http://apt.ubuntu.com/p/desktop-webmail

And put the following in file /usr/share/applications/desktop-webmail.desktop:

[Desktop Entry]
Encoding=UTF-8
Name=Desktop Webmail
GenericName=Email
Comment=Compose email in browser
Comment[de]=EMail in Browser schreiben
Exec=desktop-webmail %U
Icon=desktop-webmail
Terminal=false
Type=Application
StartupNotify=true
Categories=Application;Network;Email
MimeType=x-scheme-handler/mailto
X-Ayatana-Desktop-Shortcuts=Compose

[Compose Shortcut Group]
Name=Compose New Message
Exec=desktop-webmail mailto:%U
TargetEnvironment=Messaging Menu;Unity

The latest version of GNOME Gmail is compatible with GNOME 3. Available at:

  • http://sourceforge.net/projects/gnome-gmail/files/

or enable the PPA referenced at:

  • https://launchpad.net/~daves/+archive/daves

If you use the version in the PPA, remember that Preferred Applications is in the System Info utility now.