Just when you think Taylor Swift has reached the pinnacle of her career, she breaks the glass ceiling and heads further up. For the second time in three years, the 21-year-old was named the top-selling artist of the year by Billboard and Nielsen Soundscan, with more than 4.4 million albums sold in 2010. (Who says CDs are dead?) Taylor also received the title in 2008, while her 'Fearless' album was the biggest-selling CD in 2009.

The icing on the cake is that for the second year in a row, Taylor is Billboard's most-played artist in all genres with more than 1.128 million airplay detections in 2010.

What does Taylor contribute all this success to? "You write about things nobody knows you went through," Taylor admitted to The Boot, explaining that she's more comfortable putting her personal memories to music than she is talking about them in interviews. "I don't know any other way of writing songs than writing detailed songs that are stories in musical form ... My main focus when I'm writing a song is the person I'm writing it about, what they're going to think of it and them knowing what I feel about them. A lot of times, they don't know exactly what I felt. Somehow I feel more comfortable saying it all to them in a song ... that many more people are going to hear than if I just sent a text message! [laughs] But that's just how I feel more comfortable expressing myself."

The 'Mine' singer also remains the top-selling artist in music history with more than 34 million tracks sold to date. She holds the No. 1 position on Billboard's Top Selling Digital Artists chart. In addition, this week her latest release 'Speak Now' spends its fifth week atop Billboard's all-genre Top 200 Albums chart.

The superstar's career sales now exceed 19 million albums and 33 million song downloads.

And let's not forget that Forbes named the songstress to it's list of Top 20 highest-earning celebs of 2010. With an estimated $45 million, Taylor came in at No. 19 on the list, which included Oprah Winfrey, Sandra Bullock, Lady Gaga and Tiger Woods.

Starting 2011 out on the right foot, Taylor received the People's Choice Award for Top Country Artist from Sir Elton John Wednesday (January 5).

Taylor kicks off her world tour February 9 in Singapore and heads stateside May 27 with a two-day stop in Omaha, Neb. Details can be found here.

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