If it works and it isn't obtrusive... I don't care. We've been having advertising like this in movies and TV for FOREVER. The fact that they can swap out brands between views of the same episode just means more flexible targeted marketing. Maybe I love pepsi but not diet pepsi. now they can have characters drinking diet pepsi looking super refreshed so maybe I want to try it. At least that's the hope. And I could care less.
It's all well and good until someone changes out all of the soda can textures for penis's. Then those shows take on a whole new meaning.