[kalleboo]

> The problem is that 'extensible' is often used as code for "able to immediately upgrade to the spec I actually want while paying the least possible to Apple".

Although on one hand that was a valid market segmentation strategy. Enthusiasts can afford the base spec model and upgrade it, and "Pros" (as defined by this new model - people with unlimited corporate expense accounts) will spec their machine with Apple so that it's warrantied and supported.