I just can't. Not because I think she'll do something so outlandish that there's no way I could predict it.
But, because, as horrible as it sounds, I can't imagine her being alive in ten years. She's got that quality, like Elvis, like Marilyn Monroe, like John Lennon, like River Phoenix. To me, she's just going to burn as brightly as she can before she burns out before her time.
Also, compare these two pictures of her. One is from two years ago, where she looks like a normal(ish) pop star. The other is from a couple of months ago, looking like she hasn't eaten in months. Combine that with the partying and lack of eating she admits to, and it's not an equation for longevity.
Lady Gaga circa 2009
Lady Gaga circa 2011