I am looking at both solutions too. Some deciding factors for me wil be:
PSD Pros
-size & weight
-battery life (in most cases)
-cost (though the nice new ones are pricey)
Notebook Pros
-Way more uses - don't think I need to list them all
-Can to PP with them, even if it is just to check a few things out
-Burn DVD's on the spot for people
I think it comes down to whether your preference is size and ultraportability or whether you would like to do more with the files (and other things).
With the low cost of CF cards now, and to look at things from a storage only POV, just having 10-20 GB of cards gives you great storage and is extremely portable, even compared to a PSD.
I know, choice, choices, choices.
I am 90% sure my purchase will be a notebook. I am looking at a IBM/Leveno ThinkPad T60 with a 15" UXGA (1600x1200) IPS/FlexView Screen, 2 GB of RAM, 2G processor. Much, much more expensive but it will work great for PP and I could use it for business purposes too.