I have this suspicion that the lately renamed Zuckerbook company will build the worst kind of dystopian corporate controlled virtual prison.
You can only do and say what ZuckerFace allows you do do and say and anything not to their liking will be banned.
Intrusive advertising all over the place and your every movement, word and chat sent to advertisers.
Then if you behave in "good" according to Zuckerbook, things go well, when you are a bit of a rebel, things go bad, eventually they start selling the ability to manipulate people to other companies (much like they did on ZuckerBook for "research").
I would much prefer to enjoy something such as Second Life (which I used for years), where you can pay and be the actual customer, not the product.
Yes, you meet the worst of people in an open setting but you also get to meet the best of people and the rest of people.
I guess it will all come down to, do you like doing exactly what some ZuckerFace like character does and be under their control for "free" and maybe "safer"? or do you want to take risks like in the real world, pay your way and be able to enjoy doing things the way you want.
I'm guessing in near future where you own nothing but rent everything from your corporate overlords, they will let you enjoy the virtual world to distract you from the horrible hovel of a corporate owned beehive apartment you are forced to live in.