Facebook adds phonebook - what it means for you

When I logged into Facebook a few mins ago I was presented with a feed item stating
"Name of friend" has changed her phone number to "123-456-789" - It's been added to your phonebook. This seems to be a new feature to me and definitely an interesting addition. It raises two questions to me:
1) Does this change the way we make friends on Facebook? I currently have a "friends plus network" policy on Facebook - and all these people could now get orderly access to phone numbers; unless you mark yours private (which, quick estimate, only 1/3 or so of my Facebook friends have done). Interesting privacy implications
2) In principle, this is a great feature - but can I sync it with outlook/entourage/plaxo/etc.?

I hope Facebook will keep on expanding this, integrate Jajah and really turn it into a "utility" feature. Let me know your thoughts on this.