Apple x86 transition: a roadmap

Originally announced to be completed in 2007, the CPU transition from PPC to x86 will be effectively finished by the end of 2006, as announced by Steve Jobs 2 weeks ago.
Of course, it is a real change in strategy, transforming an original 18 month transition into a 12 months sprint. And Apple can not afford to loose this race.
This change has been entirely decided by Apple, and probably Steve Jobs is behind it. They have decided to unveil the Yonah with the current top of the line models, advertising "how fast this Intel CPU is superior to the PPC being replaced". Indeed in this case, for a non "Geek" mac customer, how to make the difference, and more importantly why would he still buy a G4- or G5-based Mac?
So to make such a change in its original strategy, Apple must be confident in its new roadmap, and has probably well evaluated the main risk : having PPC-based machine sale rate dropping strongly following the first release of MacIntel. Of course the iPod and iTMS are providing enough cash-in to partially support such potential decline in PPC-based computer sales; but the much more define or clear roadmap provided by Intel is certainly also supporting this new strategy (IBM and Motorola have never been able to provide reliable CPU roadmap).
For us Mac users, this new strategy is also a good point. The risk of a bad surprise in the near future is probably really low; and we will also know, based on Intel roadmap, what to expect for future revisions. So no more big positive surprise? Intel roadmaps are usually available for 6 to 18 months forecast, so we will also be able to better plan our decision to buy or not a current model (even though, Pentium 4 roadmap has been not really good in predicting the real outcome).
Netburst technology is dead, as the Pentium 4. The new Intel's technology is based on an entire new micro-architecture, based on a much deeper integration of the CPU/motherboard chipset couple allowing parallelization and enhanced performance per Watts.
Hereafter, we are going to "play" a dangerous game: predicting the date and future models to be released. This is based on facts, Intel’s roadmaps, hypothesis and also our long "love-story" with Apple.
The first Intel CPU to be used is the Yonah, also known as Core Duo. Apple has taken the risk to be the first to deliver a Core Duo-based desktop computer with the new iMac, iMacIntel. This is well done, considering that the Yonah architecture (Sonoma) seems to have some energy management issue that could explain why the MacBook Pro 15.4" are delay.
The fact that Apple did not release a 17" MacBook Pro could be due to the Core Duo high-end availability (PC manufacturers have also requested this CPU from Intel). When the availability will improve, the 17" model will for sure be announced.
For the iBook and mac mini, the Core Duo is too expensive, so one has to wait till the single core Yonah, Core Solo, will be available. This processor is in fact a Core Duo with one core not fulfilling qualification tests and subsequently deactivated. This CPU should be available within 1 to 2 months, so the x86-based iBook and Mac mini should appear within the same time range.
Then which x86 processor(s) will be replacing the G5 in Powermac and Xserve?
Here again Intel roadmaps allow us to design a calendar and define the possible hardware parts. In the S2 2006, Intel should release its new desktop architecture platforms supporting the Conroe and the Xeon WoodCrest.
And here comes our second hypothesis. Aapple has never proposed an Xserve based on a CPU that is performing better than those found in Powermac. So, not to follow PC manufacturers, Apple might replace the current G5/IBM PPC970 in both PM and Xserve not with the P4 replacement CPU, but with the Xeon WoodCrest.
The price would of course be higher, but the performance range would probably be worth it. Indeed the Xeon has a much larger memory bandwidth, a bigger cache and a more advanced 64 bits management technology.
Based on currently available roadmap, Apple could announce at the WWDC 2007 the new Xeon-based PM and Xserve, with an effective availability for the AppleExpo on September 2006 (as it was always the case for the G5-based models).
At the same time, Yonah successor should be also there, the Merom; and we should already see the second revision of the MacBook Pro, delivering a much powerful notebook, giving then access of the x86-iBook and Mac mini to the dual core Yonah, Core duo.
2006 will for sure be for the Mac a really important year, full of new hardware models.