Updating iPhone 3G to iOS 4

Apple iPhone - Updating iPhone 3G to iOS 4

My son is trying to update iOS 3 to 4 on his iPhone 3G. He gets a message on his MacBook that says he will lose all his media content when he does the update and to be sure to do the update on the computer on which he has all his media that he normally uses to sync the iPhone. I've updated an iPh 3GS and an iPad to iOS 4 before this. The sequence I've seen is that the new OS is downloaded to the computer, and then, if the iPhone is connected, it will automatically update the phone. If not, you can attach and download onto the phone later. Never have I seen this message previously.

1) What actually happens when we download the iOS 4 update in terms of media content (movies, photos, music)? The update obviously d/loads to the computer, but does it then wipe the media content, or only when it (new OS) is transferred to the phone?
2) If we have the identical media content on the phone and computer prior to the new OS downloading, what is left (if anything) on the phone and computer after the phone is updated to new OS?

This is probably pretty basic, but this message we received was not especially clear.

iPhone
If I could scream via this message any other way except by typing in all caps,
I'd do so, but since that's typically not my style, I'll just say this: don't do it.

I had a 3G and upgraded it to the 4 software. It slowed down my phone TREMENDOUSLY. And others that I have spoken with that have upgraded the 3G have had the same problems (no less than 5 people). My coworker has a 3GS that he upgraded without a problem, but for some reason, the 3G doesn't like that upgrade. I hope he hasn't actually done it as of yet.

I just got the 4G about a month ago and am in love.

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Thanks, for your wisdom. I had seen some earlier discussion about this when the iOS 4 update came out but didn't pay much attention, as we didn't have a 3G at the time.

Any other similar experience about putting iOS 4 on a 3G, or should I just bite the bullet (or the Apple) and get him a 3GS or 4? I hope you all have an entertaining and safe New Year's Eve (if you haven't had it already...................US Central Time here).

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Don't upgrade 3g to iOS4. It physically does not have the memory necessary to work well.

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I upgraded my iPhone 3g to iOS 4 and it was slow. That was a while back. I recently upgraded to 4.2 and now it runs smoothly.