Google Goes Black for the Day

I must say I thought my computer was playing up this morning - I went to my Google search page and it went completely black. On closer inspection I found the line:

We've turned the lights out. Now it's your turn - Earth Hour

Apparently,

Google users in the United Kingdom will notice today that we "turned the lights out" on the Google.co.uk homepage as a gesture to raise awareness of a worldwide energy conservation effort called Earth Hour.

It will all culminate in Earth Hour, where people around the world are invited to turn their lights off for one hour (8-9 pm on Saturday night in the UK).

It doesn't look though like Google.com, based in the country that wastes more energy that any other country on earth, is following suit!