My workflow is a bit different since it is Nikon based. I generally don't use Lightroom. I'm invested in a Nikon based workflow using View NX2, Capture NX2, Photo Mechanic, plugins like Nik's Color Efex and Silver Efex.
I download images using Nikon Transfer - embedded in View NX2. During downloading I create a new folder for every download. Folders typically have the location name or client name for commercial work, the full date, and a 3 digit sequential number for when I have more than one download in a single day. Files have a similar name plus a non-repeating sequential number. That lets me know when every image was shot, where, and what folder the image is in so I can find similar images if needed. My folders are named something like this
Smokies 2012/Smokies_20120417_001
and my images something like this -
Smokies_20120417_0107819
After downloading I rate all images in View NX2. I use a star rating - 1 star for misfires or completely missed focus, 2 stars for a significant flaw, 3 stars for a keeper - technically okay but may be lacking something (this is my safety net - I keep these so I don't stress over borderline images), 4 stars are good images considered for sharing, editing, printing, etc. and 5 stars are the exceptional images of which there are very few per year.
I am in the process of shifting the above download and rating steps to Photo Mechanic.
Once all images are rated, I make a final review of the 1 and 2 star images and then discard them. These files don't need to take any space on my hard drive.
One note - I try to be appropriately critical. If I only have 5 images of something unusual, I'm more likely to rate them all a 3. But if I have 1000 bird images, something as small as a poor background or wrong head position - even lack of a catchlight - may mean it is rated 2 and discarded. Signage and description indicators are always rated a 3.
Then I move to Photo Mechanic and apply keywords to all images. I use structured keywords for all images. Later I may review and add keywords for some images, but I try to get everything keyworded quickly.
The above steps are completed the day I shoot the images. Everything happens before bed.
At this point I am ready for any editing. I start by tagging only the 4 or 5 rated images I plan to edit. We are talking a very small number - typically 2-5% of my images. I may make minor edits in View NX2 to understand the potential of an image. That includes minor corrections to exposure, shadow recovery, and highlight protection. For web posts or sharing on Facebook, after a few minor edits I simply resize and convert to a JPEG. Small web JPEG images are all kept in a single folder on my computer since I tend to go back to them for multiple uses. I normally use Photo Mechanic for conversion to JPEG - it easily handles resizing, changing the color space to sRGB, setting the appropriate quality level, and watermarking (if desired) in a single step.
Further edits take place in Capture NX2 - all with the original NEF. Since edits are all lossless, I work with the original file all the way. My goal is to create master images - subsequent steps would only be output specific such as resizing or sharpening for print. I change the color tag to another color when I am finished with editing in Capture NX2. If I need to create a TIFF for use in Silver Efex, I keep it with the NEF in the same folder.
After editing, all images are backed up in two places. The folder goes into a parent folder that contains all images for that location or client. Within that folder, I may group folders by year - Smokies/Smokies 2012/Smokies_20120417_001. After verifying that I have two backup copies, the files are deleted from my computer. If I have an action required for some images, I delete all but those images. I try to have everything edited and backed up within a few days of the shoot.
I have more than 100,000 images using this approach. It's pretty stable, but I am planning a couple of changes. As I mentioned, I am going to move my download and renaming to Photo Mechanic. I do want a catalog capability like Lightroom, but given my workflow I am planning to use Photo Mechanic's catalog when it is released this year. I own Lightroom 4, Photoshop CS5, and Elements, but I rarely use them. The uses are for specific situations and tools.