Hello - This is Dennis and I'd like to help sort through some of the confusion of iCloud. As far as your mobile phone goes - do you have pages installed there too ( I assume it is an iPhone )?
yes. it is an iphone4
One other question - on your Mac are you running OSX LION? Now with the email. Even though Apple automatically creates a unique name when you first log in to iCloud (for example - "email@example.com" ) you do not have to use it in your day to day correspondence; it is their unique identifier for the iCloud account. If you were to use the iCloud.Com to send an email, the receiver would see it came from "firstname.lastname@example.org".
On your phone, you can still list your current email as the default account.