Here are the top 20 users and their most recent Tweets
1. Katy Perry, singer, 46,561,179
2. Justin Bieber, singer, 46,526,319
3. Lady Gaga, singer, 40,383,118
4. Barack Obama, President of the United States, 39,214,102
5. Taylor Swift, singer, 36,167,890
6. YouTube, video sharing site, 35,643,583
7. Britney Spears, singer, 33,795,005
8. Rihanna, singer, 32,369,513
9. Instagram, social photo site, 28,756,616
10. Justin Timberlake, singer, 27,936,121
11. Twitter, the social media site's official account, 26,310,573
12. Jennifer Lopez, singer, 24,958,876
13. Ellen DeGeneres, talk show host, 23,324,423
14. Shakira, singer, 22,657,147
15. Cristiano Ronaldo, footballer, 22,388,208
16. Oprah Winfrey, TV presenter, 21,865,247
17. P!nk, singer, 20,595,888
18. Demetria Lovato, singer, 19,656,389
19. Kim Kardashian, reality TV star, 18,675,863
20. Adele, singer, 18,339,044
