According to a report on TG Daily, we could be looking at a smaller, cooler (and less inclined to Red Rings of Death) Xbox in 2009.
Following the predicted all 65 nm Jasper platform version of Microsoft's gaming box, which is apparently due in August, the report states, "A more dramatic and perhaps visible change will happen next year."
It states that that the Taiwan Semiconductor Manufacturing Company (TSMC) "plans to begin producing the Valhalla chip, which will be the foundation of the mid-cycle refresh of the Xbox 360, thus called ‘Xbox 2.5’ or simply ‘Xbox 540’ (360+180), in fall of 2009."
Because the Valhalla is apparently "more than a die-shrink and end up as a system-on-a-chip design. This change is likely to enable to redesign the Xbox 360 casing and go towards a slim-design."
It also appears that Microsoft is taking the whole RRoD seriously for the rumoured new design, "Several people close to the cooling industry told us that Microsoft approached them and asked for better and cheaper cooling than what is used in the Xbox 360 right now."
Obviously, the Microsoft Entertainment and Devices division has not confirmed or denied any rumour and/or speculation regarding a new, slimmer iteration of its platform. It still wants to be able to sell Xbox 360s well into 2009 but equally cannot slam to door on suppliers nor can it give the impression to investors or internal opposition that it is not seeking to lower cost and encourage new purchasers for the Xbox.
Source: TG Daily