Here is something to think about with Stumbleupon. A lot of bloggers use it, myself included. But here is one thing I’ve noticed: a higher bounce rate on any page that is stumbled.

This could affect your SEO on the long run. How?

Assuming you are using google analytics, and assuming google factors things like visitor time and bounce rate, you could be setting yourself up for trouble. If someone is “stumbling” along, they might be going through 10-15 sites a minute, until something catches your eye. What does that mean for you? It means they only stay on your site for 5-10 seconds. And this is logged in your stats.