I wrote a post last year about Twitter theory, and presented on it too so I thought I'd compare how Google Buzz fits in with them or not.
Flow
Buzz is a flow but it does show an unread count, and it's in your email inbox so the implicit pressure to read is there. You're not cued to dip in and out. Also, all replies come to your main inbox, privileging them over the flow from those you chose to follow.
Faces
There are faces of people next to the root Buzzes, tapping into the subtle nuances of trust we all carry in our heads, but not by the replies, making those 'comments from strangers' even more alien.
Phatic
The phatic feel of Twitter is partially there, but at the launch there was much talk of Google 'hiding the irrelevant' so the social gestures where we groom each other may be tidied away by an uncomprehending machine.
The replies from faceless strangers flooding your inbox if you respond to anyone with a large following will put people off interacting socially. The feeling of talking intimately to those you know is replaced by something closer to the 'naked in the school lunchroom' nightmare.
Following
Buzz does pick up Twitters asymmetric following model, and indeed adds a way to create private Buzzes for small groups, both key features. However, these are undermined by the confusing editing process. The Follower/Following editing is only in pop-up javascript dialogs on your Buzz in gmail and Google Profile pages, and because of the auto-follow onboarding, rather opaque. The groups editing is in Google Contacts, but that doesn't show the Followers, Following, Chat Friends, Latitude or other subgroups. There is also no way to see just conversations with those groups.
The overall effect makes it feel more like a Mornington Crescent server than Twitter. I made a Mornington Crescent Buzz account; it seems to fit.
Publics
Twitter's natural view is different for each of us, and is of those we have chosen. We each have our own public that we see and we address.
The subtlety is that the publics are semi-overlapping - not everyone we can see will hear us, as they don't necessarily follow us, and they may not dip into the stream in time to catch the evanescent ripples in the flow that our remark started. To see responses to us from those we don't follow, we have to click the Mentions tab. However, as our view is of those we choose to follow, our emotional response is set by that, and we behave more civilly in return.
Buzz reverses this. The general comments from friends are in the Buzz tab, but anyone can use '@' to mention you, forcing the whole conversational thread into your inbox. Similarly, if you comment on someone else's Buzz, any further updates to the web show up in your main email inbox. The tragedy of the comments ensues, where annoying people can take over the discussion, and their replies are privileged twice over those you choose to follow.
This is the YouTube comments problem yet magnified; when all hear the words of one, the conversation often decays.
Mutual media
By bringing in Twitter,blogs, Google Reader shared items, photos and other Activity Streams feeds, Buzz has the potential to be a way to connect the loosely coupled flows those of us who live in the listening Web to the email dwellers who may left behind. By each reading whom we choose to and passing on some of it to others, we are each others media, we are the synapses in the global brain of the web of thought and conversation. Although we each only touch a local part of it, ideas can travel a long way.
If the prioritisation of secondary commentary and poking over collated ideas can be reversed in Buzz, this could be made to work.
Small world networks
Social connections are a small-world network locally strongly-connected, but spreading globally in a small number of jumps. The email graph that Buzz taps into may be a worse model of real world social networks that articulated SNS's like Facebook, but it could be improved if the following and editing models are fixed.
Buzz's promise is that it builds on Activity Streams and other open standards, so it could help encourage others to do this better.