Nobody already started this poll? Okay, I will.
So, what dya think happened in the end? I'll give you an Other option in case anyone has alternative theories other than the obvious,
My take is this: since Moll had a "magic" top that would tell her whether she was in a dream, her assessment of whether she was in a dream or not must have been accurate (assuming the movie is playing fair with the "rule" about the top) and if she thought she was still in a dream, I say she was right. At some point after she "woke up," she spun the top and it didn't stop on its own, leading to only one sensible conclusion: jump off a ledge (and frame your stupid pigheaded husband for your murder so he'll kill himself or at the very least, be executed).
Dom putting the idea in her mind that she's in a dream isn't what caused her to kill herself. Just because you have an idea, regardless of where it comes from, you can always change your mind. Inception isn't mind control and it doesn't destroy free will.
Okay, let's hear from the peanut gallery!