The two things are:
1. some calculated stats about Pinterest (then compared with Twitter at same time in existence), such as:
Read the whole thing for more.
* Pinterest is retaining and engaging users as much as 2-3x as efficiently as Twitter was at a similar time in its history.
* Pins link to a tremendously large universe of sites. Etsy is the most popular source of pin content, but it only represents about 3% of pins.
* Over 80% of pins are re-pins, demonstrating the tremendous virality at work in the Pinterest community. To contrast, a study done at a similar time in Twitter’s history showed that only about 1.4% of tweets were retweets.
* The quality of the average new user (as defined by their level of engagement and likelihood to remain active) is high but declining. Users who have joined in recent months are 2-3x less active during their first month than the users that came before them.
2. how they acquired the data and made calculations.
We wrote some simple scripts to identify random users who joined at varying times in the company’s history and download their complete history of pins to conduct cohort analysis. We also pulled several hundred thousand additional pins from the general user population. All told, we ended up with a database of nearly one million pins.
Thanks to our old friend the central limit theorem, we’re confident that our sizable random samples are representative of the greater population they were pulled from. We should caveat, however, that there is always a risk of sampling bias. Since Pinterest doesn’t use auto-incrementing IDs, we had to get creative about identifying random users and pins. We identified user names based on common dictionary words and then expanded to general-population pins by guessing at ID numbers in numeric proximity to the pins of those core users.
All in all it's an interesting glimpse into a social site providing an information taste that may be of value to marketers...with a quiet mention of give it a try with your own company’s data, RJMetrics is offering free 30-day trials for a limited time.
Of course others including some webdevs have been taking similar 'peeks' inside sites for years...all it takes is a competent programmer and some computers. What is different is that such folks tended to keep quiet especially about how they do the voodoo they do...
Why? one of a number of reasons is because it's not only about how the site itself is doing but identifying the power/influential users (and that is not always obvious)... why? because of marketing leverage, because often with social an oblique approach is the low risk high return marketing route.
Regardless, all in all, a nice useful info taste surrounding a soft service offering, plus a hint of how to do it yourself given knowledge and resources.