the social networking site. Mixi heavily uses open source: Linux, Apache, MySQL, and Perl. It uses several hundred MySQL servers. Mixi also uses Tokyo Cabinet NoSQL database. A term "Mixi Fatigue ()" has been coined to describe the feeling of becoming tired of Mixi, voicing a desire to discontinue using the service, and finally deciding to terminate an account. Mixi added the feature to upload your own video content, along with the ability to post content from YouTube. The corporate headquarters are on the seventh floor of the Shibuya Scramble Square (渋谷スクランブルスクエア, JA) in Shibuya, Tokyo. History Mixi has enjoyed a steady growth in its userbase. In 2005, the website had more than one million users, and less than a year later, it had more than five million users. The site had more than 10 million users in February 2007, and as of July 2010, more than 30 million. This number includes deleted and multiple accounts. Celebrity accounts In 2008, Mixi began "Celebrity Accounts" in which celebrities who are on the social networking site are allowed to surpass the 1000-friend limit and potentially have an unlimited number of followers. Many popular figures have "Celebrity Accounts" such as actress, model, singer Anna Tsuchiya, producer and rapper Shing02, Akihabara idol Haruko Momoi and countless others including fictional character Arsène Lupin III from the series of the same name. Mixi maintained an official list of these accounts. In 2011, Mixi announced that it would end "Celebrity Accounts" and replace the function with a new service, "Mixi page". Terms of use In early 2008, Mixi announced a plan to revise their terms of use. The changes, which were supposed to take effect as of April 1, 2008, included a section that appeared to grant Mixi unrestricted ownership to all user generated content. In particular, the proposed changes to Clause 18 stated: "By posting information, including diaries and the like, on this service, users grant the service the unrestricted right to use said information (whether in the form of reproduction, publication, distribution, translation, modification or the like) without compensation." However, the clause was never implemented, apparently due to user protests. The relevant portion of the terms of use currently states that "all rights (including copyright and personal-usage rights) for content belong to the user that created it." In December 2008, Mixi discouraged the use of the site for dating, prohibiting users from "using Mixi mainly