If you discount the advancements in display, processor, storage, and battery technologies, I think the best notebook Apple ever made is the aluminum PowerBook G4 with removable battery, user upgradable RAM, storage (even the optical drive), and Wi-Fi. I do have a deep fondness for the first Mac I ever purchased, Titanium PowerBook G4, but the paint peeled off within a year and it looked nasty afterward.Still the best MacBook ever made.
But yeah, technically speaking, PowerBooks aren't MacBooks, so I agree with your sentiment.