I'm all for reducing freeloading, but there other things to consider:

1. Rating people on their uploads wouldn't work - I could put the latest top 5 pop albums in my library and probably get a great score. However, if I share a file that is a little more obsure, but is still useful nonetheless, then I wouldn't get as many hits. Why would you want to have a hall of fame for people who have uploaded the most files? See point 3 for consequences.

2. There is a lot of talk about 'useful' files - but a useful file to one individual may not necessarily be useful to another. The variety of files on the network is one of its strongest points.

3. I think much of that 'economics' theory could have been condensed into a single line - "why doesn't LimeWire implement a ratio scheme." - it promotes quantity and not quality (how long have I been telling my girlfriend that it's the other way around?!). I personally, don't think that ratio's work - they exclude new joiners to the network from getting involved and they encourage people to d/l for the sake of it, just to improve their score. That would cause precious bandwidth to be wasted.

4. I don't think that the current anti-freeloader feature is too bad - it penalises freeloading (good) but lets some requests get through, so if you're new, then you might stand a chance of finding something (good). But, I wonder how many people have abused this feature and instantly set to the maximum integer allowed (bad)? What about an anti-greedy-b***ard feature?