My computer just won't do the update to ios5. It stays on "backing up" for over 3 hours. Anyway if I do the update at a friends comp I know I will lose my apps. But they should all sync back again when I sync to my computer right?
If you back up all the time and you're sure all your stuff is in iTunes you can cancel the back up by clicking the the "x" to the right of the progress bar. It will cancel the back up and move on to the next step ... this is from my experience. I'm not a Mac genius.