Here are my observations so far:
Buzz is better than FriendFeed because Google is treating it as a consumption tool rather than a destination site (by placing it in Gmail rather than hosting it on a public page). FriendFeed should have always been treated this way. Some people got confused and started hosting public discussions on FriendFeed.
That being said, though, I've long said that news and sharing is not the same as an email inbox and those sorts of items should not be 'marked as read' but rather stream by in an ambient way.
While Buzz is in fact a stream, it is its own tab that you have to focus on rather than a sidebar you can ignore (at least as far as I can tell right now).
How it affects Publishers (and Echo)
So, the publisher spends the time and money to create the content and Buzz/Google get the engagement/monetization inside Gmail.
For some reason, all these aggregators think that they need to create content to be of value. I disagree. I long for a pure aggregator that does not generate any of its own content such as comments, likes, shares etc.
That being said, however, the more places we have to engage with content the more reasons there are for Echo to exist so that publishers can re-assemble all that conversation and engagement back on their sites.
Note that they don't have a 'Follow' button - it's using synaptic connections to determine who you care about. Very cool! I worry though that there might not be enough controls for the user to override the assumptions.
Already, Marshall is calling it the savior of open standards. I don't think Open Standards need to be saved - but they certainly have all the buzz words on their site so that's promising.
That's it for now, maybe more later when I've had a chance to play with it.
Update: After playing with it this morning, and reading a little more, it's clear that this is actually Jaiku reborn (not FriendFeed), because the Jaiku team were involved in building it. They deserve a lot of credit for inventing much of this stuff in the first place - long before FriendFeed.
Also, having used it only for an hour, the unread count on the Buzz tab is driving me nuts. It shouldn't be there. It's a stream not an inbox. Also it makes no sense why I can't display buzz in a sidebar on the right side of my primary Gmail inbox view. That would be ideal.
It's also funny to me that some people have tried to give Chris Messina credit for Buzz even though he's been at Google for no more than a month. They clearly don't understand how long and hard it is to build product. Messina is good, but he aint that good :)