I have experienced this as well, but only for two apps. All the rest disappeared from the list after being updated. But the same two apps have remained in there even after newer update notifications have been processed and completed.
I suspect that it's a bug with those apps and the App Store app. Even after updating to 7.0.2 tonight those same two apps remained in the App Store update list, with the Open button.
I recently read on some other forums that these will stay in the App Store for two weeks and then go away. People have set the calendar on their phones to say the phone is two week ahead or more, and those items will disappear from the App Store listing.
It's an annoyance because it's a change from earlier versions of iOS.
I think that the reason Apple did this was to work in conjunction with automatic App updates. Since you would not know when an App gets updated when they are done automatically, this will keep a historical list for the last two weeks.