is Facebook really viable longterm?

why does Facebook constantly send potential friends lists to email? with 1 billion users in sight, how could anything go wrong?

perhaps a real look at users, ad click through rates, purchases because of the ads, and frequency of use per user would reveal weaknesses.

consider that instagram owned by Facebook removed high quality images from twitter. twitter pics must be a threat. and with hundreds of millions of users why are high quality photos on twitter a cause for concern?

let's all think about this for a bit. somewhere out there is the innovator with the idea to reinvent social platforms. please start your own business. Facebook google and the like want to pay you great out of college salaries so they can own your ideas. they took chances. so should you.