Tumblr is growing at a rapid pace. They hit 6 million users and just hit about 1.5 billion pageviews per month (Quantcast). About a year ago, Tumblr saw about 255 million pageviews. In November of last year, it was up to 420 million pageviews.
Tumblr is now a top 50 website in the U.S. About 6.25 million Tumblr users are based in the U.S. The U.S. users are posting 4.5 million posts per day. A year ago Tumblr was creating 650,000 new posts per day.
Tumblr founder David Karp said that there is more new features coming soon. Users can choose between the English, French, Japanese, German, and Italian language for each of their themes.
Tumblr also recently updated their iPhone application to support video. You can choose to upload an existing video or record a new one to upload.
[Traffic stats via TechCrunch]