The numbers in the table clearly show how fast Twitter has grown in the last year. The 1,000 most followed acounts in the world now have an average amount of followers of 1.2 million. In the middle of March the Global top-1000 reached a combined total of 1 billion followers, which means an average of 1 million followers each.
The second largest language is Portuguese, with an average number of followers of almost 196 thousand. The popularity of the Portuguese language is almost entirely caused by the popularity of Twitter in Brazil.
The third language, with an average of almost 154 thousand followers, is Spanish. From the Spanish Twopcharts it can be observed that Spanish tweeting Twitter users come from a wide variety of locations like Spain, Argentina, Mexico, Colombia and Venezuela.
With an average of more than 84 thousand followers for the Top-1000 accounts, Twitter is also extremely popular in Indonesia.
Disclaimer: The table only shows languages tracked by Twopcharts. Other languages may or may not be more widely used than the ones represented here. For example the Arabic language is only tracked since March 2011. At the end of June the average number of followers for the Arabic Top-1000 accounts was about 11 thousand. Other languages, like Japanese, are also very popular, but are currently not tracked by Twopcharts.