A report from AllThingsD tackles comScore’s latest data regarding mobile audience measurement report, which hasn’t been released yet.  The report stated that in August, Instagram had an average of 7.3 million daily active users or DAUs, while Twitter only has 6.868 million DAUs during the same period.

This is quite interesting, given the fact that Twitter, according to comScore, had approximately 29 million unique U.S. smartphone-based visitors in August, while Instagram only had 22 million.

The report also stated that Instagram users were spending more time on the photo-sharing site than on Twitter.  Instagram users spend an average of 257.0 minutes on the site while Twitter users only spend an average of 169.9 minutes.

Though longer time spent on the Facebook-owned site may mean it is becoming more popular than Twitter, we have to realized that Instagram shows people photos – as in photos ranging from a simple sepia-toned milkshake to artsy photos that could take a few seconds or even a minute for people to appreciate.  Unlike  Twitter, which is focused on words that you can read in under 10 seconds or links that redirect you to other sites.

Twitter’s made several attempts to increase engagement on its site, offering expanded views to see photos and videos in a preview instead of redirecting to the original site.  Even as Twitter tries to become more like a standard social network, it may not bode well for a platform that’s fundamentally different from anything we’ve seen before.

In any case, an increase in site usage, whatever the cause may be, is still something important.  It just may help validate Facebook’s $1 billion purchase price for Instagram.  The question now is, how can Facebook monetize on the popularity of Instagram’s photo-centric experience?

Twitter, too, is working on finding the right balance for social media and monetization, constantly tweaking their business model around paid and promoted tweets to optimize their user streams.