StumbleUpon Compared
What sets StumbleUpon apart from other sources of traffic?
StumbleUpon vs Google
People searching for something on Google want to find something in particular. You can try all you want, but if you aren't offering what someone is looking for, they won't be interested. That being said, if you are offering something with a very particular appeal, Google might be your only hope. Search engines will always have their place in a marketing plan, and cannot be replaced outright by StumbleUpon, but they can be supplemented significantly by them.
Stumblers are not looking for anything in particular. Most of the time, they are just bored. They want to be entertained, and if you are capable of holding their attention for long enough, you can turn them into promotors of your site. By simply clicking the Thumbs-up button, stumblers effectively cast votes for your website. The more votes, the more stumblers will see your site.
You can see how, by providing quality content, this can become a periodic cycle, generating loads and loads of traffic over time.
Stumblers are looking for content with broad appeal, so they are open for almost anything worth its salt. This is one of the major advantages over search engine marketing. You can take a visitor who initially had no plan, but is now suddenly interested in your website. The trick is converting them to customers or subscribers.
The other major advantage over Google is that stumblers aren't given a small excerpt from your content to decide whether or not they want to go any further, they are given your entire content, by itself. You have their undivided attention. This gives you a whole lot more flexibility in terms of achieving conversions.
StumbleUpon vs Digg
This also applies to most social bookmarking websites. The general trend for most social bookmarking websites is an initial spike of traffic, followed by a quick tapering off. While the spike may be larger than the StumbleUpon spikes, StumbleUpon traffic can be more consistent over time. The reason for this is the periodic cycle mentioned above.
The reason this does not occur with most social bookmarking sites is that they are designed to capture breaking news stories, not unique, timeless content. Though Digg is working on expanding into StumbleUpon's area of expertise, StumbleUpon has a distinct advantage, in having been in the field of content delivery for much longer.
And again, it is the difference between displaying a list of summaries and an entire page of content. A good way to compare all three would be the television analogy. Social bookmarking sites are like reading the front pages of TV guide, search engines are like reading the directory of the TV guide, and StumbleUpon is like channel-surfing.