I don't kow whether you consider that traction, or sampling. It does illustate the value of a huge installed base, huge name recognition and a cloud-based service, though. The day Google decided to go "live," it got noticed and used by enough people to create a substantial number of entries.
Also, one thing about "perpetual beta," which Google tends to rely on when launching new products, is that it does actually work. One of the "gotchas" Google Buzz rather quickly uncovered was a potential privacy issue. Under some circumstances, it might be possible for Buzz users to discover "follower" email addresses.
Google coders jumped on the problem and apparently have it fixed. And Google already is talking about launching an independent Buzz site that is not linked to Gmail accounts, to further address the issue. That's a fairly interesting illustration of how powerful social mechanisms are, though. Within three days, a potential privacy issues was uncovered and fixed, and enough users seem to indicate they want a version not linked to Gmail that Google already is considering that option.
