If Microsoft does a redesign it'll be to move the fucking GPU out from under the DVD drive... jebus you'd think even a software company would figure out that it was a bad idea from the start

Uhhh.... wait... what???

360's still here... there's still time to do that if they want to. Other than that, there's only been one other system they've had... so... ummm.... yea...

Have they still not done that yet? Its not like they'd need a huge redesign for that. They could do it stealthily, keeping the same case and everything.

Who's saying they won't?  So, at some point they may or they may not... but it's unlikely.

First... the main problem of the redesign is attachements like the HDD.  Attachments become no longer interchangable... which was suppose to be a big selling point of the detachable HDD. 

Second... the costs involved in the redesign.  Yes,  eventually a smaller product saves money... but think about the RD involved in the redesign and the setup of a new production line. 

Will the new design actually be worth the cost savings and totally segmenting the current user base?

There are ways to redesign the console yet without breaking HDD addon compatibility.

There was a roadmap leak quite a while ago and after the jaspers they're supposed to fuse the gpu and the cpu into a single slab of silicon, probably once they reach a new node. That's when they'll redesign it, if they do it. But I'd bet 10$ they will redesign it for the Natal bundle.