Rick Diamond, Getty Images for CMT

As if becoming a best-selling author, reality television personality and Las Vegas headlining resident wasn't enough, Shania Twain has now added best-selling female in country music to her impressive list of 2011 accomplishments, with 75 million albums sold worldwide.

On the heels of her official induction as country music's leading lady, Shania has released the aptly-titled 'Today Is Your Day,' her first single in six years. Co-produced with Nashville producer Nathan Chapman (Taylor Swift), the self-empowerment anthem is available for download exclusively through iTunes, and is already No. 2 on the iTunes country songs chart.

"The purpose of writing 'Today Is Your Day' in the first place was self-inspiration," Shania explains. "I was talking to myself and saying, "Today is your day. You can do it!" But the decision to even write the song and share it was a big decision for me, to find myself as a songwriter again, independently, for the very first time after all these years."

The self-imposed hiatus may have rattled her confidence, but the songwriter admits the new single became her personal mantra, and the obvious song choice to represent her OWN Network reality series, 'Why Not? With Shania Twain.'

"The lyrics started flowing," she says. "It was genuinely a melody that's cheering me up. It became the natural theme song of the series."

Already planning your Las Vegas getaway to catch the Shania live? Tickets go on sale to the public Sunday, June 19 at 1:00 PM ET. Fans can visit www.shaniainvegas.com or call 1-800-745-3000 for more info.

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