Because I'm a Harvard alum and have been an alum interviewer, I have been asked many times to estimate individual CC members' chances, something that I do NOT do. However, as my holiday gift to everyone, I'm posting this so you can estimate your own chances.
Your chances of admission: about 7 in 100 (based on Harvard's acceptance rate this year). If you're an international applicant, your chances probably are less than that particularly if you come from a country like China, Korea or India, which has many outstanding students who apply to Harvard. Your chances probably are better than 7 in 100 if you come from a country that has few applicants to Harvard. You would know better than I would what those countries are. As is the case for everyone except probably the qualified offspring of multimillionaire donors, Harvard still is a longshot. Note: It's also a longshot for legacies. Many excellent legacies are rejected. I even know URM legacies who have been rejected.
If you have posted a chances thread on CC or have asked CC members to read your essays, your chances of admission to Harvard are probably less than 1 in 100 because your behavior here indicates you lack the confidence and critical thinking skills that Harvard seeks. This is true even if someone on CC predicted you'd easily be accepted or said that your essay was amazing.
If you've chosen your ECs and summer activities by selecting things that you think will impress Harvard, your chances of admission are probably less than 1 in 500. Harvard wants students who follow their own passions, not students who try to fit themselves into a Harvard box or whose only passion is getting a Harvard admission.
If you've ever asked CC members what activities you should participate in so you can impress Harvard or other colleges, your chances of admission are probably 1 in 1,000. You lack the initiative, confidence, creativity, passion and critical thinking skills that impress Harvard admissions officers.
If you are taking notes on this post and while calculating your Harvard chances, you can stop calculating now. Your chances of admission are 1 in a million.