Workflow and organization.
I keep all of my photos on disk in a folder structure that starts with the year with sub-folders per month. I use Nikon Transfer 2 to rename and transfer into the month folders sub-folders named by date and sequence number. E.g, 2011>2011-02>2011-02-03_01
Using this format makes it easy to avoid name collisions and is a good basic organization.
Once Nikon Transfer is complete I open Aperture 3 and import the folder to a project. I set Aperture to manage the masters in their current location (reference library). I have faces turned off because I don't use the feature and it takes disk space. I've limited the preview size to within 1200x1200. Again this manages disk space.
Aperture 3 uses generated preview jpgs to preview and to share. I typically share that size anyway. When I upload to flickr i use full size as a third off-site backup.
In aperture, I use a multiple-pass organization technique. I go through each image and mark either -1 to get rid of the image, 3 stars to keep and occasionally a 1 meaning probably delete. I then go back through the 3 stars and mark as 4 stars any I like enough to share and 5 star for the best album quality images. I'll also demote some to two stars or lower for eventual deletes.
I then delete all remaining -1 and 1 stars. I advise being aggressive in your selection. I have kept too many similar or low quality images and need clean them out.
Next for each 4 and 5 star images I locate in finder, open and edit in Capture NX2. I save the NEF then save as jpg the processed version. I then import the new jpg into the aperture project. If you open to Capture NX2 from within Aperture it sends over a TIFF version and you loose the value of raw.
I then run my backup sync and time machine for the local drive.
Now I re-format the memory card.
Monthly I move the working folder to the main library on my USB drive. You can do this via aperture or in finder than re-associate in aperture.
Up next, Backup, Redundancy and Disaster Recovery.