So I went digging, and it seems that there are not many Windows-based RSS readers that can handle the image part. So if you are announcing your photocasts to the world, you may want to let them know they need a compatable RSS reader. One I found which is free is Blog Navigator. If anyone finds a Windows RSS reader that will display the images inline, too, that would be great.
Before you publish, make sure you have sensible descriptions or file names for the images -- or else all the viwer sees is the image file name. I have to go through all 196 images in my photocast now to correct the names.

