I would also be interested in Bluetooth tethering to iPad. In my country tehtering was never an issue, it did never occur to the local providers to disable or limit tethering in any way. Every provider offers unlimited HSDPA internet plan for approx. $15/month (typically with some fair play policy), but I can't tether my 3GS to my iPad... 🙁
I don't want to buy separate sims to every gadget I own. Its frustrating that
seemingly the various limitations imposed by AT&T affects the software capabilities and design choices of Apple's mobile products, so we Europoeans have to suffer as well 🙂 (or Apple does not want to allow 3G tethering, not to cannibalize the market of the more expensive 3G enabled iPads...).