Billboard Year-End Hot 100 songs of 2009

Billboard magazine each year releases a Top Hot 100 songs of the year, counted from the first week of November to the final week in October. The 2009 list was dominated by The Black Eyed Peas and Lady Gaga, who shared the top four spots. On 27 December, DJ Earworm released a mashup video to YouTube entitled "Blame It On The Pop", featuring the top twenty-five songs from the list, as he had also done the previous two years. The video quickly went viral, and received four million views in little over a week.

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