Are you sure about that. I mean do we know for certain that Sony takes bigger losses with PS3 than MS with X360 atleast in the western markets. I'm personally not so sure about that. We are looking at a rather large price difference between these systems, and all the estimates of the manufacturing costs that I have seen have something fishy about them.
Well let's take the Premium 360 and the 20Gb PS3. Assuming that all other differences are negligible and/or cancel each other out (I certainly doubt that at this point the PS3 components are cheaper), doesn't the BluRay drive alone make the 100$ difference already?
What I mean is that for justifying Microsoft making money on peripherals, the 360 should actually be more expensive comparatively than the PS3, minus the difference of the BluRay price. This means that either the BluRay component costs a lot less than 100$, or the components in the 360 cost Microsoft a lot more than the components of the PS3 cost Sony. And looking at the respective console's components, where the PS3 tends to have the more expensive parts in general, I don't see this happening.
Having said that, I do think that Sony will get the PS3's cost close to their selling price quite fast. But I also think that the 360 has reached that point already.
To return back on topic, mind you, a 512mb card is definitely a step up from a 64mb, so in general this is a step forwards. But as posted above, the price per mb is still ... ehm ... rather steep ... and you'd be silly not to get a HDD at this point.