Actually, pretty well. I'm pleased. Not only that, but my new workflow is more efficient than my old one. Background details are in this post. Here's what I do:
1. All images are shot RAW. I set white balance to auto and ignore it. With those CR2 RAW files (12 bits of color) I can fix the color balance later.I get significantly better results than I've been getting with in-camera JPG, and this workflow is really quick.
2. I import all images into my 'intake' iPhoto Library. (I use iPhoto Library Manager to switch libraries, but if you option-click launch iPhoto it will ask for the Library location.)
3. Edit in iPhoto, cropping, adjust color balance, sharpness, etc. (I plan to buy Noise Ninja, that will change my workflow, more later).
4. Export as JPG (this drops color bits to 8, so it's important that the white balance has been fixed.
5. Rename using a A Better Finder Rename (this is not necessary for most.)
6. Import into my main Library, add comments, etc.
7. Put Intake Library images in the trash. Next time I use it I'll empty the trash.
Update 5/3/06: Alas, I've come across a very annoying bug. I set iPhoto to save edited raw as TIFF 16bit/channel. When I did this and exported JPG the metadata was missing. GRRRRRRRRRR. I've turned off the 'save edited RAW as TIFF' option.