I'm getting both at launch for a simple reason - if the rumors are true, they're both going to be PC architecture. Which means we can see a repeat of what happened on the original Xbox which got hacked wide open. The initial ones were easy, the Microsoft slowly closed all the holes in later revisions.
There's no reason to expect the first models to not have similar flaws. Later revs will probably fix the holes.
There's no reason to expect the first models to not have similar flaws. Later revs will probably fix the holes.