Taking a chapter out of Apple's fully integrated "system", the others (Google, Facebook, Amazon, etc.) are now in a full throttle war to get you to buy-in to their ecosystem. It's a simple formula...how much of your on-line experience stays in one portal? In order to secure more of your attention (translates into sales), each of these organizations must build both physical and on-line systems to make you feel completely comfortable. It needs to appeal to your tastes and be really, really simple and intuitive...a la Apple. Google isn't adding YouTube movies to sell movies per se. It's another reason for you to stay at home on the Google ecosystem. Why go to Netflix?
Kindle Fire, Nook, iPad...designed to keep you in the system.
Not so long ago, the measuring stick was which site you had your browser home page set to. Now, it's which ecosystem do you spend most of your time in.