I really think we'll be seeing Intel Mac preview machines for the masses. Apple made an OS X beta release for the public. I'm sure they're more than willing to sell boxes with Intel chips and profit from the big demand from them. I'm predicting the same exact dev. configuration kit to be made available for around $1299. Shipping with the latest Mac OS X 10.4.3 for Intel

As for
casing, Apple will go with the small-form factor (like the Shuttle) since it doesn't offer one in this config. Apple wants this box to be faster than the Mac mini and probably the iMac, but slower than the basic updated G5 towers.
Powerbooks will of course receive their G5 chips, running at 1.6 - 2GHz with 512MB memory baseline and a nice X600 graphics chip across the board.
Powermacs will go dual dual cores (4 logical processors?) at 2 - 2.4GHz each.
iPod will
not go video. As widely rumoured, same price-point, 40GB and 80GB. They'll announce a special Nano discount during the holiday season, and further bring up the prices of flash memory (by selling more units of the Nano). We're talking about
$179 and $229 now.
Airport Express Video will go 802.11n but is backward compatible with current g hardware. Apple wants to be the first few in the industry to go 'n'. Apple introduces iFlicks to store, convert, rip and organise your video collection to be streamed wirelessly.
Bluetooth Mighty Mouse is introduced, bringing down the base wired MM to $39.