Although it easily could have turned into a random social media site lost among a sea of similar speedy blogging platforms that have emerged in the last year, Tumblr hasn't tumbled.
In fact, Tumblr is nearing the 10 billionth-post mark as it now retains almost 28 million blogs and sees over 37 million posts a day.
Take a look at exact metrics current as of 10:25AM PT on Friday, September 2:
Royal Pingdom has worked out a number of time units in which 37.5 million posts can break down to from as low as a second and then back up to a year. The web monitoring site also predicts that Tumblr will surpass 10 billion posts within a week and then 20 billion in nine months should it stay on this growth rate.
Tumblr's growth has accelerated incredibly even just in the last few months. The Next Web reports that Tumblr had racked up over 5 billion posts and approximately 17.5 million blogs by May 1, 2011.
Tumblr fits in somewhere between WordPress and Twitter among the major social blogging sites. However, it stands apart as one can add more text and some graphics, but Tumblr posts don't usually warrant anything as long in word count as one might see on WordPress. Somehow, that model of being able to "share anything" has worked towards Tumblr's success.
Not much has come close to it in terms of traffic, active users and the platform itself -- with the exception of Google+. Google's foray into social networking is still on an invite-only basis, but it also lets users share just about anything one might want to share online (photos, videos, long or short snippets of text, links, etc.), but it doesn't have much of a tie into other social networks like Tumblr does with Twitter and Flickr.
One could argue that Facebook has these same features too, but blogging at any length isn't as much of a popular feature on Facebook as it is on Tumblr or even Google+ already. Plus, Tumblr and Google+ both have much cleaner layouts, which also lends to the idea of how similar they might be.
However, once Google+ grows, it's inevitable that such additional features from other social media sites will happen. Thus, while it would be awhile from now, we might be seeing Google+ challenging Tumblr eventually. But at the pace that Tumblr is growing, it will be difficult for anyone to catch them.