Thaius said:
..in the case of a letter, your words are what matters. To ascribe importance on any other aspect of it is frivolous and stupid...
Not really, no, Thaius. We adjust our content depending on our audience but the medium we choose has just as strong an impact as the content.
Consider the valentine. Make the content a simple sentence, "Will you be mine, oh sweet one?", and change the way it's sent.
Email: The sentence arrives in an inbox, unadorned and plain, at eleven o'clock at night just before the receiver goes to bed, making the receiver wonder just how serious the sender is being.
Mail: The sentence arrives in a card, signed by the sender, sealed with a kiss. The receiver gets choked up and puts the card in a place of prominence, to remember such a gift.
Phone: The sentence arrives in low, husky tones, making the receiver shiver with excitement and ask about the possibility of sex with the sender.
Stone: The sentence arrives attached to a rock through the receiver's window, punctuated by screeching tires, leaving the receiver confused, appalled, and more than a little frightened.
Words have meaning, yes, but how they are communicated can change that meaning dramatically.