I have to say as a constant replacer of Apples that in comparison with other similarly priced laptops from premium lines of non-Apple makers, the level of depreciation is pretty much the same as any other machine. The resale thing is a myth, like many things ascribed to Apple hardware. It's worth bearing in mind that the vulnerability of Apples to very noticeable cosmetic damage means that unless the machine is babied, you may prejudice your resale value even more than a slightly cheaper Windows PC... especially if you actually use it like a normal machine.
Whether it gets babied is another matter entirely. Many people do seem to acquire computer-babying skills after they buy an Apple. Many also seem to betray the reduction in reasoning skills after being inducted into the Apple Cult while patting themselves on the back but that's something else.
I'd say along with Lenovo's T and X lines, Dell's Latitude and Precision lines are, as well as HP's Elitebooks, equally viable options for very long-lived machines. All of them feature conservative design, conservative build quality with no envelope-pushing for 'sex factor'... and long standard warranties. It's true that no machine is built like flagship notebooks used to be, but the above are probably the closest you'll get.
If you are of the reasonably (but not to Apple level) babying persuasion, then you might like to consider Sony's top tiers. They're still made in Japan and quality is high. However Sony do probably push engineering envelopes more than anyone else (and the fact that they're made in Japan is part of what allows them to do so without Apple's 'Rev.A, B and occasionally C issues'), and support does leave a lot to be desired on the rare occasions they do go wrong... so there's still an element of risk.
