My bad — maybe.
Earlier today, I reported that Google Buzz, Google’s new social sharing service, was sending less traffic than FriendFeed, a service which has been a ghost town in recent months. It turns out there’s probably a good explanation for this. You see, in January, Google started defaulting all Gmail traffic to the HTTPS (secure) version of its domain. Previously, it was defaulting to the regular HTTP (unsecure) domain. As a result of this change, all traffic referrers are scrubbed before being picked up by services like Google Analytics.
I didn’t realize the change would cause such a scrubbing, but it makes sense. Google’s Matt Cutts pointed it out earlier (in Buzz, appropriately), and looking at our logs, it does, in fact, appear that in January (when the change was made) traffic from the mail.google.com domain plummeted. This was before Buzz ever existed.
This is interesting because it means that Google Buzz is essentially a social service that you can’t track the effectiveness of for your own site. Of course, given that so much of Twitter is run through its API, measuring Twitter traffic by the twitter.com domain is also flawed.
Still, looking over the overall numbers, it would seem that aside from a rise in referrals from the usual suspects (Twitter.com, Facebook.com, etc), we haven’t seen a huge bump from some unknown anomaly out there — which, you’d assume, would be Buzz. So I’m still not convinced that it’s actually sending a lot of traffic our way. But, admittedly, it’s hard to know for sure, because like a black hole, its existence must be inferred.