I agree, at that age any observation is purely conjectural. In my case, with less than four months of age my daughter would have a fit for nearly anything including us just trying to move or acomodate her position to get more confortable.

At that age they are just passively interacting with the world, so it would really make no difference it they stare at the TV, a mobile toy or the parents interacting with each other. Whichever is most colorful or resambles a face is more likely to attract attention. It's only after three months or so that you can say that the baby can somewhat interact with anything.