people that buy the core 360 probably cant afford or dont want all the accessories that it has to offer. they can buy it piece by piece as they can afford it/ need it. whereas the ps3, you need 500 dollars up front to buy it, not having any choice in the decision.
if you buy a core system, that seems kinda worthless to me, no hd is really hard to get by with. i couldnt imagine that. with all the updates out there now, it would suck with no hd
They also forgot to add a HD cable to the PS3 price seeing as its not included with the PS3, Bluray is useless without it. The 360 bundle already includes this.