Update on "backlight only glows in centre"
My A1260 had the same problem. Someone dropped some sugary substance on the keyboard before I got it.
I thought the lights were behind the keys and that the circuitry was damaged by the liquid. I pulled the keyboard of and fully apart (tricky job and very time consuming)
As it turns out (as Thomas pointed out) the backlight system is spectacular! there are 3 layers on the bottom of the keyboard just for the backlight system.
From bottom up here is a description.
1 ) White plastic layer. This contains a small circuit and 4 LED. These are sealed so they cannot be damaged by a simple spill
2 ) Transparent Perspex layer: The 4 Leds on the white layer fit into 4 slots on this perspex sheet. This sheet has several white dots that serve the purpose of reflecting the light that comes from the diodes at 90 degrees up to the key. the density of the white dots vary to ensure equal illumination of all the keys. Brillianyt idea!
3) a thin plastic transparent layer with a black grid whose purpose it is to absorb the light that would otherwise be reflected in between the key spaces.
The reason my keyboard was only illuminated in the centre is not because the circuitry or faulty LEDs but simly because the liguid had altered the refraction/reflection qualities of the clean perspex layer.
I simply immersed them in warm water for an hour or so and then gently dried them with a cold airflow from a hair dryer
You must pay particular attention to the 4 slots on the perspex layer. This forms a little pocket where liquids will coleect and dry, thereby altering the light reflected /refracted.
The sweet substance had made many keys sticky so I took the whole keyboard apart and washed it in warm water. The key contacts are sealed in between 2 glued silicon layers. No water gets in.
The job took a few hours but now my keyboard is like brand new!
Thanks to Thomas and to iFix it