In fact, it drives more traffic referrals than any other social media site.
As an online marketer we all know that a Facebook post or needless to say a Tweet has an extremely short life span. A tweet lives for a few minutes, Twitter is fast, and I keep repeating the phrase that my ex-boss once told me "Twitter should be what CNN uses in their tag line, Be The First To Know".
Facebook have their own lovely alogithm that is supported by several likes, your interaction history with each user, time of posting e.t.c. A Facebook post may live for a few hours.
But after 24 hours your post is far down on any users newsfeed.
On StumbleUpon it keeps travelling.
A page shared on StumbleUpon has after 400 hours just gained half of the engagement it will ever get. A Facebook post reaches that point after about 3 hours.
2,5 million webpages are added each month to StumbleUpon. I personally added 15 in the last hour. That's the effect SU has on you, it makes you stick around, it's sticky, it's good.
Check out the infographic for yourself and install the browser toolbar and start adding your favourite webpages and blog posts!