Actually, for me the experience has been exactly opposite. From the first day I updated my iPad (3) to iOS 6, the App Store has been sluggish as hell - up until a few days ago, that is. Maybe Apple has optimized it on their end.😕
It's really slow regardless of what device you use. I have a Macbook pro, iphone 4s, ipad4 and Mac mini. They are all slow. Must be a site specific problem.