It seems to be similar but not quite the same as the yellowing of the top cases.

Flickr photoset showing the surface of the battery. (I wish I had taken more photos).

Apple is blaming the damage on a “chemical spill” and so far getting them to repair it is proving difficult. To be honest I think this well could be a flaw with the machine and it would be to Apple’s benefit (as well as mine obviously) for them to get to the bottom of exactly what caused. The computer hasn’t left my side since we bought it, so I think I might have noticed a “chemical spill”.

If anyone is experiencing this or has heard of anything like it please let me know.

I was hoping that purchasing a Macbook would mean I wouldn’t be affected by the slew of problems affecting the Macbook Pros. But it seems like the Macbooks have problems of their own.

Update:

Thanks to Alan for pointing me at this thread on the Apple discussions board. Looks like i am not alone. Hopefully the fact that someone else is seeing this problem will mean Apple won’t try to blame me for exposing the Macbook to a “chemical spill” any longer.