Ahh, the beauty of standard framework.
This bit caught my attention:
But there's also a bookmarks feature that's new in Preview 3.0.1 (shipping with Tiger) that allows you to add a bookmark to any PDF, or intriguingly any image, or your computer and reopen it from Preview.
You could think of it almost like a browser bookmarks menu. If you're halfway through a huge text document and need a break, you can hit
Command+Dto add a bookmark. The same applies for images you might want to use often.
Preview's keywords are not viewable in iPhoto. Maybe an AppleScript will fix that?