Bridgestone have decided that the grooves will be coloured green for the Fuji GP, a marketing ploy to show their "green" credentials.
One small problem, the green grooves stay when the tyres are the softer compound.. which makes the white groove VERY difficult to distinguish.
Or do I need an eye test?
http://www.itv-f1.com/photo.aspx?IM_ID=50515&PG_ID=22