Yeah, I haven't really considered using it, myself, but I figured it was a good thing to mention. As for memory, I was referring to ram, but I know the program would of course download on to a hard drive. That's a different matter than memory, though.
As for peer-to-peer networks, you are right that it happens more on P2P networks than any other network infrastructure.. But do note there are only a handful of other infrastructures and you're mixing P2P file sharing with P2P processing. Same method, but slightly different usage and concept.
Definitely some good points to highlight, though. It's good to see someone give a review that looks at this in a realistic point of view instead of the classic "omg, I have money, now come join the bandwagon" mentality. Props for that one!