The most important for me is:

-Wall/grid with thumbnails in Large Screen Mode. When user clicks on thumbnail it sends them to what there is now in Juicebox - an image with some thumbnails below (or above)

Also I would love to see:
- Tagging images and search box, optionally tag cloud,

Last but not least:
- Advanced Theft protection - I dream about better solution than disable right click.

Thanks!