1. Beyoncé's "Single Ladies (Put A Ring On It)"...
Sony Music
2. ...and Lady Gaga's "Just Dance" were the No. 1 songs in the country...and also the No. 1 songs that got everyone running to the dance floor.
UMG
3. Lady Gaga also rocked her iconic bow hair.
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4. The Kings of Leon dominated alternative radio with their smash hit, "Sex on Fire."
Sony Music
5. Taylor Swift had the No. 1 album in the country...
Big Machine
6. ...and she also performed on SNL for the first time (in case you forgot, Neil Patrick Harris hosted).
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7. Chris Pratt and Anna Faris announced they were engaged.
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8. Fergie and Josh Duhamel got married.
Us Weekly
9. Prince Harry and Chelsy Davy broke up after dating for five years.
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10. Joaquin Phoenix said he was quitting acting to pursue a rap career.
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11. Kelly Rowland announced she would no longer be rep'd by her long-time manager, Mathew Knowles (aka Beyoncé's dad).
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12. Faye Dunaway and Hilary Duff started their feud after Faye reportedly said, "Couldn’t they at least cast a real actress?" upon hearing Hilary would play "Bonnie" in a Bonnie & Clyde remake (a role that Faye immortalized).
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13. Jessica Simpson got the internet in a tizzy after wearing these infamous jeans:
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14. Speaking, of the internet, January 2009 was also when "David After Dentist" was uploaded onto YouTube.
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15. The Oscar nominations were announced and, as expected, Heath Ledger received a posthumous nomination for Best Supporting Actor for his role as the Joker in The Dark Knight.
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16. Katy Perry said she was taking a vow of celibacy, but took it back the next day.
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17. The 66th Golden Globes award show aired, and some of the big winners were Slumdog Millionaire for Best Motion-Picture Drama...
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18. ...Mad Men for Best Television Series – Drama...
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19. ...and 30 Rock for Best Television Series – Musical or Comedy (Tina Fey and Alec Baldwin also won Best Performances Globes in a Television Series – Musical or Comedy for their performances on the show).
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20. Kara DioGuardi made her debut as a judge on the eighth season of American Idol.
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21. Paul Blart: Mall Cop and Taken were among the movies released into theaters that month.
Columbia Pictures, 20th Century Fox
22. The Miracle on the Hudson happened.
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23. And finally, Barack Obama was sworn in as the 44th President of the United States of America.
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