For the majority of my photos, the red eye was not detected at all, or the red eye was detected, but not all red eyes in the photo were fixed automatically. In these cases, the one-click Red Eye Removal tool in the Editor still does the job quite nicely--although it is a bit of a drag to launch the editor just to fix a little red eye. The auto-detection is rather slow as well. For the most part, it's faster just to use the manual tool.
When red eye is corrected automatically, the corrected photo is saved in a version set and you can revert back to the untouched original photo if you need to. Auto Red Eye fix can also be disabled on the fly from the Photo Downloader if you don't want it slowing down the import process, or when you know the batch contains no red eye.
