Because it's a 17W TDP i7, which indicates Atom architecture inside. The article is currently comparing an 18W TDP Fusion chip with an 8W TDP (old) Atom part with way less RAM, which is actually showing a great performance from the Atom chip to me.
No, the i7 indicates it is the i7 (Nehalem) architecture. Not an Atom chip. Also, even though the TDP rating is the same, it will consume quite a bit more power. In exchange, it is much faster.