In his post Industry analyst Benoit Felten questions whether the telcos are B.S.-ing us with this notion of “bandwidth hogs” From his post:

Unfortunately, to the best of our knowledge, the way that telcos identify the Bandwidth Hogs is not by monitoring if they cause unfair traffic congestion for other users. No, they just measure the total data downloaded per user, list the top 5% and call them hogs.

And:

TCP/IP is by definition an egalitarian protocol. Implemented well, it should result in an equal distribution of available bandwidth in the operator’s network between end-users; so the concept of a bandwidth hog is by definition an impossibility. An end-user can download all his access line will sustain when the network is comparatively empty, but as soon as it fills up from other users’ traffic, his own download (or upload) rate will diminish until it’s no bigger than what anyone else gets.

Also see: Congestion Neutrality by Herman Wagter that explains more of the nuts and bolts of how TCP/IP works. (Via Ars Techica)