> > for example, developers aren't permitted to touch the second cpu,
> > there is no such restriction on the open source side.
>
> I don't understand... why would Sony do something that would (seemingly) cripple
> their product? Is there some severe downside to using this second CPU that Sony
> wants to avoid, or is it something more sinister, like intentionally crippling
> 3rd party games so that Sony's own games sell better or something?
>

Might be something as innocent as they know they'll get a new/faster/cheaper processor soon, and they're just using this at the moment as a back up. When they get a new single processor that that's faster cheaper, they can swap that round for minimal effort, if people are coding to the metal assuming there's always going to be a 2nd cpu it's going to mess up their compatibility.
Not a bad idea really, keeps things upgradable internally.