Racoon beat me to it. It's Vault boy. The pip boy is the computer we all wear out in the wasteland.
Or at least it is in fallout 3 and NV. I think it's still technically wrist mounted in 1 and 2 but you get what I mean.
What are we even talking about here? It's nice artwork and as I said before: "perhaps the Vault-Boy used the Pip-Boy to approve the dosage of radium".
When you see a doctor or whatever on an item you have purchased and it says: "scientifically proven!", are you the first to say: "hey there, now wait a minute! That guys isn't
science!"?
The Vault-Boy
uses the Pip-Boy to approve the beverage (like the scientist uses science). But a piece of equipment can't give you ye olde thumbs up, so the Vault-Boy is inserted to deliver the message.
In more plain reasoning:
- Pip-Boy in text on advertisement to convince our reasoning, logical side
- Vault-Boy to personalize the product and pressure our emotional side