The resale values changed when Apple switched to Intel. We can't just disguise Mac performance by talking about Megahertz Myth, or "G4s and G5s are faster at floating point, blah blah blah...." anymore. We're on a level playing field with Windows computer hardware, so rather than making Macs harder to price evaluate, this switch to Intel has made it easier to compare hardware specs, as pricing of the parts used in a Mac is more transparent today than it has ever been.
That, and there are more Macs out there today than ever before. There's lots of used Macs, so pricing has to be more competitive (ie: lower).
