MacBook: better screen, keyboard, speakers, battery life, milled aluminum unibody, has airdrop/App Store.
Nobody remembers that brand as being "IBM's laptops", they don't have that to borrow value against, they should take care of the ThinkPad line's reputation.
The Mac just works. The only time the touchpad doesn't work is when you need pixel precise selection like in photo editing, and even then it outshines all Windows touchpads.
All Windows laptops I've had look outdated after two years. I've had three Macbooks, the previous two 5 and 7 years, and both didn't look outdated, not even used
The body, magsafe, touchpad, no stupid privacy settings, disk encryption, no OS licensing - this laptop works for me. With Windows it's always waiting for the time that it doesn't work like expected or doesn't work at all.