Ok, had to chime in with the problem/solution...apparently there is a counter problem in either the 3.0 update or the firmware in general...once your 'Saved Photos' hits 0999.png your images are saved although will be invisible to your ipod...ugh
The solution (until there is a firmware update) is to reset the counter...go grab iphonebrowser 1.91 -
http://code.google.com/p/iphonebrowser/downloads/list
Install and run iphonebrowser (with your ipod connected)...under DCIM/.MISC (in the left pane) delete 'info.plist' in the right pane...disconnect and restart your ipod...this should have reset your ipod (image counter) and the next image saved will be 'IMG_0001.png'
WARNING: I had to delete/transfer any images already in 'Saved Folders' prior to applying the fix to get it to work although haven't looked back since!
See you at 0999.png 🙂