Hi,

Can anyone define for me what this actually does and why you would want to use it?

Is it a redeploy of the predefined applications?

Look at service books being the provisioning for your device from the carrier. Unless sowemthing changed, you need only do it once. You can have them sent as many times as you want with no harm.

Yes, it is as you described

Resending your servicebook refreashes your network service.. you can get your missing browser back, activate email, fix network problems, things like that.