I saw that too. So they're selling you a slower processor than the 13'' Air. Glad the old models are still available but I think the refub store is going to be the best place to shop.
Why does no-one on Macrumors understand a f**king thing about processors but are nevertheless more than willing to claim their opinion authoritative? They put 15w processors in the MBA but 28w in the 13" rMBP. Even at a lower clock speed the higher power processor would outperform the lower by a wide margin.