I don't use the date based system for a simple reason - I rarely need to find a photo I shot on a particular day or at a particular location. When I need to find a photo, I usually need to find a photo of a particular subject. So I group my photos by subject.
For nature photos, I have a folder for plants, birds, mammals, inverts, reptiles, amphibians and fish. In some folders I have sub-folders for the major groups, so within the Reptiles I have a subfolder of Snakes, Lizards, Crocodilians, and Turtles. In the snakes folder I have them broken up into families since I have a LOT of snake photos. Birds are broken up into orders somewhat, depending on what I have lots of photos of.
The advantage to this system is you could put all your bird shots in one folder and start adding subfolders as the need arises. So if you end up with a lot of Ardeids (Herons/Egrets), you make a new subfolder and move the Heron and Egret photos into there. The rest of your miscellaneous bird photos stay in the main "birds" folder.
The reason I like this system is that the file already has the date in it (backed up in the EXIF file) and I can put the location in as a keyword or add it to the EXIF if I wanted to search for files from a particular location.
sandboa added 147 Minutes and 39 Seconds later...Double Post Merged Below
Another interesting discussion of this was this series of posts -
http://www.texasphotoforum.com/forum...ad.php?t=92982