I would have recommended a Thinkpad a couple of years ago, but now I'd say go with the Macbook if money is not an option. If it was me, I'd get the new Haswell MBA 13" and put Linux on it.
Thinkpad quality is terrible these days, and they got rid of the good keyboard. Just do some forum searches. On the plus side, you can get a used Thinkpad for really cheap - about 1/3rd the price of the equivalent Macbook. Just make sure to get one with a warranty.