I wonder if Steve needs to move to marketing? He's done an awesome job here of highlighting one massive difference between GPlus and Facebook - that you can really publish publicly to the whole world, the way the web was intended.
Here are a couple of examples:
via a Facebook page called 'notes': http://www.facebook.com/notes/web20/robert-scoble-on-cloud-c...
via user Scoble's wall: http://www.facebook.com/RobertScoble/posts/10150358391274655.
No Facebook account needed to view either.
Facebook started primarily as a website for college students to share privately with their friends.
Google Plus started by emphasizing that you can choose who you want to share with (including the public) and shipped with a "subscribe-like" feature that allowed technical people to add many of the same tech celebrities that they were following on Twitter. Since it takes awhile to convert one's friends to a new service, for many tech people, reading public posts by these other tech people became the prominent way they use the service.
You can mostly do the same things on each site (albeit at different levels of convenience), but their beginnings help shape how people think about and use the sites.
http://blip.tv/oreilly-open-source-convention/oscon-2007-ste...