1. Circles: Slick grouping capabilities to allow your digital life to mirror the way you behave in meatspace
2. Fast search: To allow this to be a real archive of digital interactions
3. Solid functionality: Facebook has lately been very rocky from a technical standpoint
Features that are value-add:
1. Hangouts: I'm hanging out - join me...or not. Its very passivity is what makes this work from a social-psychological standpoint
2. Integrated email / chat: Less sites to visit for this stuff
Enabling factors:
1. Massive access to users: Through brand and existing applications
2. Import networks: Streamlined mechanisms to set your network up fast
3. Relative trust: A vast number of people still like Google and want to use its products....whereas Facebook is at best considered a utility and at worst truly evil
What it could do better:
1. Formatting, layout and navigation: Not as useful and readable as Facebook's today
2. Direct messaging: Seems to have only email available (when it is available for a contact at all)
3. Events: Nonexistent on Google+ today
4. Content curation: In truth, no one does this really well today but it has the potential to be a killer app, and if anyone can do it, it's Google
Summary:
18 million users to date. A serious contender... if they can evolve the platform - very fast.