Joe Bloggs
doesn't know what an anonymous proxy is. I doubt he ever will, it will just be built into clients and you'll never need to know about it. (EarthStation5 anyone?) Probably wouldn't be too difficult to code in a WEP/WPA cracker either.
This will certainly bring 'securing your wireless router' to the forefront, after the first few people fall victim to anonymous users downloading via their connection and having their connection cut off!
There are enough legal loopholes and technological ways around this. It will be interesting to see how they get everyone to thoroughly protect their IP address from any form of abuse. As you pointed out about Joe Bloggs and his ignorance of anonymous proxies, perhaps it should be pointed out that Joe Bloggs also is usually ignorant of securing wifi routers, removing and preventing malware, preventing his kids from installing Limewire etc, etc.
Rather than forcing ISPs to police the networks, they are delegating that to customers, who by and large don't have the requisite knowledge to secure their private networks.
Childish as it may be to mention again that this is an arms race, that doesn't detract from the fact that this IS an arms race and therefore a waste of all these well-paid peoples time and our money, due to the fact that, this time the big army is composed of 'bad guys'.
I'm not taking sides here, other than to point out that this is not really the solution, because as soon as it has mass effect, it will be circumvented, either through law or through technology.
In the mean time, lots of innocent people will be affected and made victims of others 'crimes' as so often seems to be the case with monolithic companies trying to protect their (artists) Intellectual Property.
DRM didn't last either, because it inconvenienced customers who played ball, whilst having zero effect on those who didn't!