Shania Twain turns 50 today, adding another milestone to a 25-year career that's full of landmark albums, chart-topping hits and bare midriffs. To celebrate, she's gearing up for another leg of her Rock This Country tour, which will help bring her days on the road to a close. Explaining her decision to Rolling Stone Country, she said, "I want to write more music," and "I'd like to spend a lot more time doing that."