The great big G A P in the G5 product line...

why not a powermac?

what kinda stuff will he be doing that he will actually need better graphics? bc i know my parents just do the basic shit and they don't need awesome graphics, not sure if your dad is the same way or not.

freestyle,
agreed, a G5 mini would be sweet. my guess is that as soon as they make it work in the nextgen apple laptop, it'll be ported to the mini. remember, the mini is essentially iBook G4 technology, and as such it works in such a compact enclosure. so dual G4 cores, G5, G6, what have you, when it's notebook capable, then u'll likely see it ported to the mini. i could be wrong, but apple has an interest in having their product line on a G5 platform, where the 64 bit capabilities would be a common selling point.

also, while yes a G5 would be faster at compile times for iDVD projects, the beauty of OS X as well as the G4s is that waiting is less of an issue for projects given your ability to use the rest of the OS. i've noted a number of times that my iBook allows me to do any number of any other things fluidly, while video encoding, whereas my windows machine becomes largely unusable.

if it's of any reassurance, the biggest delay on iMovie is the importation process, which u may know converts the media to a raw uncompressed DV format. (btw, using quicktime on my windows machine to do an export to DV format is not notably faster, if at all, compared to the conversion process in importing to iMovie. note that when doing an export on my windows desktop i do it to a drive separate from the OS and programs, so that there's no I/O bottlenecks...and again there is little difference between my desktop and my iBook in DV conversion) beyond that, applying transitions is swift, and output (video file or iDVD export) is not laborious IMO. however, as noted, my version of "laborious" looks more at the usability of the OS while doing such encoding rather than how quickly it happens. i.e.-the idea of waiting for a project to complete, when doing so does not render my computer unusable, is much more appealing than a computer that does it slightly faster, but makes it difficult to open a new application such as arun of the mill email client.

put some 3rd party RAM in a mini...at least 512MB, preferably 1GB, and i doubt there'd be many complaints on the part of your dad.

Why don't you recommend your dad a PowerBook? You can connect the external screen on it while the pb is closed...

About those Powerbook G5 in the future I can tell you one thing: Rev A has always bugs. You've got to consider if you want a G4 which works perfect or a G5 rev a with bugs.
I'll propose you the following: buy a G4 PB with external screen (if you have lots of money the 30" ) when rev b of the G5 comes out then you can buy that one and sell your G4.
Which I would do...

pb is slow for all rendering i should know cause i won one and it jitters liek crazy on i-movie. By the way its a 1.5ghz g4 with 2 gig of ram.