I believe in iTunes, right before the update or restore, where you hit the continue button (or it could be an ok) it says something like any music, videos, or photos that sync with the device will be removed.
I'm not completely sure about this since I don't sync photos with iTunes, but if you do sync with iPhoto then all your photos will be in there. I believe there were instructions to backup all your data before running the update. Even if it didn't, that's always the last thing you do before updating any device.
this is for PC's: When you update or plug your iPhone into the computer, and it asks you where you would like to load your photos, do Microsoft WORD. It should be the last choice. It will then hook up with microsft word and "my pictures" and then just create a separate folder to put all your iPhone pics in. That's how I did it. And I'm pretty sure it said it would delete any photos when you download the update. So if you didn't save them, they are gone.