Me, Myself & iCloud
I found myself in an uncomfortable situation when updating to iOS 5. iOS 5 gave me a new @me.com account but I was never happy using it for aesthetic reasons, it never got used and I remained with gmail. I later realised @icloud.com account was being offered in iOS 6 so when I got my iCloud mail account I wanted to use it on my iPhone 5, but the default is set to send from the @me.com account.
If you want to make @icloud.com your default account rather than using @me.com here’s how:
Settings > iCloud > Account > Advanced / Mail > Allow Sending From > ‘Switch Off Your Me Account’ - Done.