this has nothing to do with ZenPhoto other than it is photo organization by a js framework.

http://extjs.com/playpen/ext-2.0-dev5/examples/organizer/organizer.html

I can see the possibilities!

Nice indeed (a bit windows style...nothing for a mac user...:-)) But I am a bit skeptical according to rely too much on this fancy javascript "playthings". I know so many people who still use older systems and browsers that this is always difficult to use.