I would say macbooks are a point in favour of the previous poster. They made some serious progress by becoming intel machines, i.e. PCs.
* An Intel chip means that I can run Linux on it and still have access to closed-source programs (Flash, Matlab, etc).
* An Intel chip makes it possible to boot Windows natively.
* An Intel chip makes it easier for Apple to maintain forward momentum without needing to goad Motorola/IBM/etc to improve their PowerPC offerings to be competitive with Intel/AMD chips.