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This is the dumb way to do it.

look on Macoshints.com for the "photo gallery" sync trick. You can still back up when you want to without changing settings and can quickly add new apps when you don't feel like waiting 2 hrs for a back up first.
 
You can try this...

I only tried this once, I just used "slide to unlock" to access the iPhone (because it was taking to long, I thought it was stuck) when it was backing up and it stopped the back up, and then synced the iPhone. This was my old 1st gen iPhone, so I was not to concerned about having to restore it.
 
I only tried this once, I just used "slide to unlock" to access the iPhone (because it was taking to long, I thought it was stuck) when it was backing up and it stopped the back up, and then synced the iPhone. This was my old 1st gen iPhone, so I was not to concerned about having to restore it.

This also works on the 3G iPhone as well! Saves me some time, especially later at night when I fall asleep waiting for the backup to finish.
 
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