[jawns]

My site, Correlated (http://www.correlated.org) has gotten >100K hits from StumbleUpon (all organic), and in my experience, it's crappy traffic.

I've looked at my site stats, and only a tiny fraction of those hits -- less than 1 percent -- results in any sort of action on the site.

Compared with traffic from practically every other referrer, that's markedly less engagement.

There are some sites, for instances, whose referral traffic results in engagement in up to 50 percent of cases, and those aren't all necessarily highly targeted audiences.

What can I infer from this?

My guess is that a lot of this StumbleUpon traffic is coming from people who are only passively using the service, as opposed to actively using it.

I would describe an active user of the service as someone who says, "Hey, I'm bored. I'll go to StumbleUpon and look for some interesting websites."

I would describe a passive user of the service as someone who, say, has it set as their homepage, so it opens up whenever they open their browser, whether or not they're actually in the mood to check out new websites.

Whatever the reason, StumbleUpon referrals are traffic that I have largely written off.

[JonnieCache]

As someone who was a university student recently, I can tell you that the standard stumbleupon usage pattern goes like this:

    1) Click stumble button
    2) Look at page for 0.5-2 seconds
    3) Stay on page if it's the kind of thing you're looking for (usually novel flash
       games or funny videos,) otherwise go back to 1.

The mouse pointer typically never leaves the stumble button during this process, we used to flick through dozens and dozens of pages like we were doing a psychoanalytic free association excercise until we found something we liked.

So yeah, not exactly high quality traffic.

[user24]

agreed. You get huge, brief spikes of largely useless traffic.

I'm not convinced there is an 'active' user of SU; I think people get into a click-the-stumble-button cycle and burn through 10s of pages a minute, meaning that most of the SU traffic is just bounces because they'll click for the next page in a matter of seconds.