Voor onze Apple vrienden kwam ik bij MacOS Rumors wat leuke info tegen over een 64-bit versie van MacOS, voor gebruik met de tevens 64-bit PPC G5, waarvan de release geplant staat in 2001:
Although OS X is being prepared for a smooth transition to the G5, due to the more than two years until Apple will have working prototypes to test on, it is difficult to make predictions as yet. One thing is certain: Apple, IBM, and Motorola have a close relationship on PowerPC development, and with Apple's continued comittment to the platform, there is no way that the latest version(s) of the Mac operating system won't be ready -- and optimized -- for the G5 when it ships.
It's important to remember that although many otherwise well-educated computer geeks take 32-bit processing vs. 64-bit processing to mean that the 64-bit processor can do twice as much work per clock cycle (by being "wider") is not at all accurate. In fact, many 64-bit processors are larger, hotter, more expensive, and may not perform dramatically better than their 32-bit counterparts in common desktop computing situations. The "bit length" of a processor is not the same thing as its "data width," and should not be taken as an indicator of overall performance without much more information.
[...] The first PowerPC to use a 64-bit Integer unit will be the G5, which will ship in 2001 at just over 1GHz with numerous architectural improvements, dramatically low power dissipation (easily used in portables!), and is expected to carry the PowerPC platform to 1.5GHz and above during its lifetime.
Check MacOS Rumors voor het complete verhaal.