Why would I want to switch from @me.com to @icloud.com? I already have an old Apple ID @gmail.com and the @me.com one. Why would I want a third?
There is no advantage.
Apple renamed their service from MobileMe to iCloud, so it is logical to change the email address to match.
You can ignore the new address if it is not required, your previous @me email will continue to function.
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