I'd hate unlimited plans ... The data leechers would stuff up any good speed left in the bandwidthnand normal users like everyone else would be worse off ...
I hate this viewpoint as it is just wrong. The way that TCP/IP works it just isn't true. In New Zealand the issue is that the unlimited people are on a separate bandwith pool.
That explanation is massivley oversimplified, but correct in one respect. Each TCP *stream* roughly gets the same amount of bandwidth on a congested network. So the user with a torrent running 50 tcp streams gets significantly more BW than your single stream video feed. So the torrent comes down (eventually) but your video is unwatchable. In other words, in a world of torrents and multi-threaded downloaders, that explanation is rubbish.
TCP isn't a magic network sharing fairy, and was never designed as such.