I hope this settles once and for all the discussions we have here - always someone throws the "in the USA there are no CAPS!"... Well, gigaom post "Want to know if you ISP is capping your data?" is a good start.
AT&T basic DSL is capped at 150GB, and Uverse at 250GB. Comcast cap is 300GB but this is being reevaluated.
There are some higher caps sure, but there are also some lower caps. And when they make a price/cap distinction between 1.5 Mbps services and faster - yes 1.5Mbps. Remember in New Zealand we don't hear much any more about speed distinctions.