Something very interesting has happened with Google indexing my images. As you may or may not know, google image search can account for 50% or more of a person's traffic depending on how well you name your images. My images were not indexing, so I optimized my robots.txt file to allow Google to index my images. However, I did not see any images being indexed.
For a completely unrelated reason, I decided to add the WP-Cache plugin, just to see if I could increase my performance. At the same time I added WP-Cache my images began to be indexed by the Google Imagebot. It seemed completely unrelated, though. I recently turned off my WP-Cache to work on my template. I forgot to turn it back on, and within 1 day my images were no longer indexed on Google. Once I turned WP-Cache back on, I have found that almost all of my images are now, once again indexed.
Does anyone know why this might occur? I have no clue. I do highly suggest using the wp-cache to see if you find this to be the case because I was blown away by the massive traffic increase. I basically got a 100% traffic bump in 4-5 days.