Unintended effects of Stumbleupon?

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.

Many SEOs theorize (myself included) that google factors in bounce rate and page time into your ranking. If they see a high bounce rate, and see that people only stay on your page for 10 seconds, they make an assumption that your site is bad, irrelevant or dangerous. By stumbling your own pages, you may be inviting this type of traffic, and might suffer a penalty in google.

I haven't done a lot of extensive testing on this, but this is a theory I have, and should be considered. Just something I was thinking about while checking over my stats the other day.

What do you guys think?
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