It might be a good idea to pull all the photos and video from your iPhone and back them up before upgrading to iOS4. It seems some people have experienced strange issues. If you search the forums at macrumors.com or discussions.apple.com for “iOS4 Camera Roll” you’ll see some threads.
In my case the dates of all the videos in the camera roll were changed to the date I installed iOS4. It doesn’t look like photos were affected.
I don’t see a way to fix this, it seems the proper date information has been wiped. My iPhone backup prior to iOS4 has already been overwritten. In my case I have about 4 months of videos that I’ll have to adjust manually if I want the right information.| Permalink