The store lists a very strange "new" white Macbook. They adopted the Geforce 9400 chipset but with DDR2 memory and it keeps firewire. I'm officially confused by that decision. I thought they were saying "firewire is dead!!!!11"
But the white Macbook is now the value leader in Apple laptops - you don't have to get a "crippled" version in the low end.
2GB of memory, 2GHz Core2 with a 1066MHz bus (dual-channel 667 is enough bandwidth to feed that and have some leftover for the graphics), DVD-RW, 120GB hard drive, same 13" screen and form factor.http://www.apple.com/macbook/white/specs.html
I expect the graphics will be a little slower, due to less overall system bandwidth, but still perform tons better than the X3100 GMA.