Using QML, the delegates (objects that hold the thumbnail and metadata) are deleted from memory when not in view (unless the developer sets a cache buffer), so the memory usage is not dependent on the number of items in the list, but instead depends on the number of items currently on screen (which is small). I have implemented a coverflow view for my QML rewrite of cuteTube, complete with transitions when switching between listview and coverflow, and I can say that scrolling performance is very nice. I'm going to prettify it to make it look closer to the N8 version. Here's a couple of screenshots of the current state: