Guys, I don't think this is BS. The Apple store usage took AT&T by surprise, now they are skeptical about this next one.
Tethering means a lot. Anyone can use Skype on their laptop driving down the highway and not pay a single penny for minutes. There is a lot for them to consider here. Portable Internet is very powerful.
Sure some people will do that but most people are already paying for minutes and data usage that they do not use and most will not be trying to use both at the same time.