[nostromo]

This isn't as true as it once was.

Google's best asset for ranking is their user data. Even if you had the exact algorithm, you couldn't game it without massive amounts of user traffic. (At least not for popular searches.)

[threeseed]

No. Their best asset is their deep understanding of what makes a page "good" and the intent behind a search query.

You could get rid of all their user data and it would still be a great search engine.