How do I map the keyboard media control keys to switch tabs instead?
You can use a private.xml like this with KeyRemap4MacBook:

&lt;?xml version="1.0"?&gt;
&lt;root&gt;
  &lt;item&gt;
    &lt;name&gt;test&lt;/name&gt;
    &lt;identifier&gt;test&lt;/identifier&gt;
    &lt;autogen&gt;__ConsumerToKey__ ConsumerKeyCode::MUSIC_PREV,
    KeyCode::BRACKET_LEFT, ModifierFlag::COMMAND_L | ModifierFlag::SHIFT_L&lt;/autogen&gt;
    &lt;autogen&gt;__ConsumerToKey__ ConsumerKeyCode::MUSIC_NEXT,
    KeyCode::BRACKET_RIGHT, ModifierFlag::COMMAND_L | ModifierFlag::SHIFT_L&lt;/autogen&gt;
  &lt;/item&gt;
&lt;/root&gt;


For some keyboards you might need to replace __ConsumerToKey__ ConsumerKeyCode::MUSIC_PREV with __KeyToKey__ KeyCode::VK_CONSUMERKEY_MUSIC_PREV.

See the source for the key code values and predefined settings.