I saw that on a different flash gallery and also in picasaweb, and thought it would be really cool if imagevue implemented that feature as well.
Right now when you enlarge an image, it burst out of the screen limits.
My suggestion is that when we click on zoom, the image window will stay the same size, and if the image doesn't fit that window then the cursor will change into a hand and we'll be able to drag the cursor to all directions to see the rest of the image.
I know it's not the easiest thing to explain but I hope you got my general idea.
What do you think? Is it possible that we see such a feature on one of imagevue's next releases?