I might have said this before, but if that is the case I'll just repeat myself

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The best thing (that is actually doable, so no dual-core G5 PB's!) Apple could do right now is this:
Move Powerbooks to 7448. Clock-speeds could be around 1.6 - 2.0Ghz. Increase the screen-resolutions, and bumb up the vid-cards. Dual-layer DVD-burners on all models. Give iBook the specs that current PowerBooks do, and maybe bumb the screen-resolutions. This would mean clock-speeds of 1.5 and 1.67Ghz, 166Mhz bus). This would give both lineups a good bumb if specs and performance.
Give PowerMac the dual-core 970MP. The lineup could start from 1x 2.4Ghz dualcore G5, continue to 2x 2.7Ghz dualcore G5 all the way to 2x 3.0Ghz Dualcore G5. Bumb up the other specs as well, move to PCI-Express if possible, and upgrade the vid-cards accordingly (current vid-cards on the PM are a joke!). Bumb the standard RAM to 1GB.
In the end, these would be relatively simple yet effective upgrades. PowerBooks would be relatively yasy upgrade, since the chip is pin-compatible. iBook would be relatively simple upgrade, since they would simply recycle their old PowerBook tech in to iBook. The hardest part would be the PCI-Express-upgrade on the PowerMac, but the PM really needs that upgrade! And if they are planning to sell the PM for over a year, they HAVE to upgrade it! PM's are supposed to be hi-end, yet AGP hasn't been hi-end in a long time! And by the time PM moves to Intel, AGP will be ancient with only obsolete vid-cards supporting it! Come on Apple, do it!
Other upgrades I would like to see: Smaller iPods with higher capacities. New Airports with video-out and wireless Firewire. Give PowerBooks and PowerMacs wireless Firewire, and maybe the iPod as well (stream your movies to the big screen). That would be very, very cool indeed. Think about it: watch DVD-movies with your Powerbook, transmit the image and sound wirelessty to airport which the outputs it through your big screen and speakers.
If Apple did these, I would think that just about everyone would be more than pleased. And, IMO, Apple COULD do these.