While this may be a more direct or open admission of a "moral" attempt to shape political outcomes, I think it's worth remembering that every other major corporation has its hand in the pot, albeit in a less direct fashion, when its board pours money into lobbyists, special interest groups, and media outlets. Sometimes for "moral" reasons, sometimes for economic reasons - but every major corporation is a political player.
As I mentioned in my other comment, we may be fooling ourselves by judging Facebook through the lens of old media or old corporations - there's been a paradigm shift and it needs to be appreciated and judged as such. A free, borderless and global communications platform and service used by 1.5 billion people simply doesn't fit into our classic models of "free speech" and "corporate personhood". I'm not sure what the best approach will be to ensuring their neutrality when it comes to their algorithms, but I think that assurance should exist, ideally in a trustless, provable fashion.
