PB 1.67 15 inch for a 20 inch core duo imac

I say no, mainly because of the PPC v Intel.

 

I say yes because they both are going for about the same price on the market (eBay, CL).

 

Under that reasoning, I'm NOT supposed to trade a Powermac G5 2.5 dual for a stock Intel iMac.../sarcasm

 

As the the PowerBook has a G4 processor, which is less powerful than a G5 which is slightly less powerful than an Intel Core Duo chip I would have thought you would go for the more powerful of the options.

But thats just my reasoning...

The iMac is more computer.

 

I agree with this. I'd probably say it's about a fair trade. the iMac will definitely be faster, but the Powerbook has 2gbs of RAM and is plenty fast itself. If you need portability, you're making a good choice.