Factom has been hyped over the last weeks and got good media therefore I spend some time to get into the project. Nevertheless, I have two questions.

As I understand it, Factom is a sidechain of Bitcoin and could be hooked to Bitcoin's blockchain and it uses the Proof-of-Existence concept. What is the advantage of buying the coins called Factoids?

According to different resources the current amount of Factoids is 8,753,502. Is this the final amount and how was this "crooked" amount defined?