You can look at the code. The secret is random. It's stored, encrypted, in your wallet. Your encrypted wallet can be stored locally in your browser or remotely in a blob vault.

As for why there is a need to have a centralized company that backs it, it's because adoption is absolutely not a sure thing. We've worked as hard was we can to design the system, develop the code, build relationships with other companies, and so on. There will come a time when Ripple no longer needs us. As people find the Ripple network useful, we hope they'll contribute the features they most need or want. We're having a developer conference in Las Vegas in about two weeks.
https://bitcointalk.org/index.php?topic=293086.0