Take this with a grain of salt, but I recently read that AT&T was throttling unlimited smart phone plans, not iPad plans, at least with 3G. So if that were true, it wouldn't be a stretch to learn that they weren't throttling iPad 4G, either. I'm on unlimited 3G on iPad and iPhone and received a standard throttling notice on my cell phone bill months ago, but I've never received one for my iPad plan (all I get is email confirmation of monthly credit card charging). I've continued to use as much data as I've wanted to on iPad, going well beyond what was indicated for throttling, but have yet to see any throttling of my use. I kept expecting them to clamp down, and wouldn't be surprised if they do, but we'll see. Meanwhile, I use my iPhone unlimited relatively little.