StumbleUpon is sending emails to users letting them know when they've submitted something that got a lot of stumbles. I'm not sure how frequently the company is doing this, or what the threshold for a successful stumble is, but I got this email last night.
I'm also not sure how long StumbleUpon has been doing this, but I've been using the service for years, and have had plenty of "successful" submissions, and this is the first time I've ever seen one of these emails. I'm used to getting content recommendations from the company via email, but it's nice to see when something you submitted made a difference without having to go to your profile and looking back on how everything has performed (by the way, maybe Klout should take StumbleUpon into account as its making all its new changes).
The email also serves as a reminder that you can actually go to your profile and look at this data. For many, StumbleUpon is probably still the service they use without actually going to the site, since it's really about visiting other sites anyway.
StumbleUpon has made changes over the past couple years to cater to more on-site engagement, though it's unclear how much people are really taking advantage of the SU site itself.
StumbleUpon does still appear to be driving plenty of traffic to sites. Shareaholic released some data a couple weeks ago showing that StumbleUpon referrals have been seeing strong growth of late.
Image via StumbleUpon