I would have to say it is very likely for Valve to add this to the game, Only problem is that this "Animated Pip-Boy" Mod/Addon has been here for 3 years. And yes, If Valve were to add this to the game. It could possibly take that long if they were trying to create it where you can see it in your Weapon Viewmodel. But Valve is usually always working on something *COUGH* Left 4 dead 3" *COUGH*

But this may take a long time, But I love the idea of this, great job ;)