A marketing analytics firm is claiming that the average tweet on branded Twitter sites is worth a little over $25.

Yep, you read that correctly; $25.62, to be precise.

The revenue estimate comes to us courtesy of SumAll, a data visualization and analytics firm.  It reached that conclusion after reviewing more than 900 of its customers’ social media program efforts.  SumAll published its findings last week in an infographic.

To those who might look at the ~$25 figure and scoff (that may be most readers), it should be noted that once the total number of people who see an individual tweet is taken into consideration, the amount of revenue gained per impression is only about one half of one penny, on average.

To put this into context, $0.005 revenue-per-impression is lower than most other marketing tools and about on par for AdWords revenues-per-impression.

The imputed revenue from tweets amounts to about 1%-2% in incremental revenues, according to SumAll’s study group.

Not surprisingly, this announcement was met with questions … and some skepticism.  Asked to explain further how SumAll came up with its results, a SumAll spokesperson replied on the company’s blog:

“… Our data comes from our own user base of over 30,000 people.  We anonymize the data first and then aggregate all the data to derive new, interesting insights from a broad population.  For this infographic, we collected data from all users who have a Twitter stream and commerce stream, and conducted some calculations to derive the value of each tweet.”

There, that should clear up matters nicely, right?

As if pre-anticipating the muffled sniggers or raised eyebrows in reaction to this “non-response response,” the blog response continued:

“This is obviously a little overgeneralized, but I hope that [it] clears some things up.”

Uh-huh.  Or as radio NPR talk show host Diane Rehm might say, “All right and we’ll leave it at that.”

The experience of our clients hasn’t approached what SumAll is reporting … but I’m interested in hearing what kind of results other companies may have experienced using Twitter as a social marketing platform.  Any particularly positive stories (or negative ones) to report?  Please share you observations here.