they're probably using compression (Score 1)

My guess would be that they'll be using some sort of compression gateway that would proxy web/pop/etc traffic. The server would compress the traffic and client software would be responsible for uncompressing. Some of the compression is lossy (such as that on images) so the consumer will see lower quality images and the extra bits wont need to be sent over the wire. It's something used by many wireless carriers to increase the perceived throughput to tethered user. To the average consumer it *looks* like it's a faster connection, when in fact it's the same real connection speed, because of compression and unecessary packets never making it to their end.