I finally managed to create some flashable zips that work, so you can move from Samsung email to Google/ICS email app much easier. All you need to do is go into manage apps, Email and clear data and cache (if any), reboot into recovery and flash ICS_EmailGoogle_update.zip. It will rename Email.apk, Exchange.apk and SocialHub.apk and install the new apks. To revert back to stock, again go to manage apps, Email and clear data and cache (if any) and boot into recovery and flash ICS_Stock_Email.zip. If you don't clear data, when you switch back and forth you will get FC's. I only use this with Exchange, so I can't verify if it works with other providers, but it works great for me.
I realize you can do all this with a rooted file explorer, but with the amount of times I seem to have to do it, this is easier...
As always, no guarantees, if your phone blows up, I'm not responsible. If you are curious, open up the zips and check out the scripts, just so you can see that I'm not deleting your system partition...