I had top score until someone got a score of 100001158 (mine being 3385. You may need to take extra measures to ensure the scores are valid and from the game.
Their site http://thislooksfun.com/ is currently unimpressive. It's noticeably slow on my broadband connection. Why? Huge background images changing on a relatively quick timer (sizes as large as 4.5mb, 7.56mb).
It's just an email gathering page, but a few minutes spent in an image editing program would give a much better first impression.
As a counter example, twittermachine (or was it tweetingmachine) creator posted a little while ago that a simple theme from theme forest increased his conversions dramatically.
This brings me back about 8 years when I was learning similar things in the wake of the dot com crash. I will go ahead and say that further learning of languages and whatnot at your age is not necessary. If it's fun, go for it. But being well rounded by exposing yourself to things outside of technology will help flex your idea muscle (brain). Steeping yourself in tech is not the best way to come up with ideas. When I want ideas, I walk around and pay attention to how the people around me use technology and how they could better use it. Just chatting with people will help greatly. Soft skills will help you in life just as much as hard skills. Attempting to learn the sum of a college education from 15-18 is going to be harder than with the help of profs/TAs, you will miss things, and you may find yourself bored once in college (I did). So unless your goal is to be the obnoxious kid in the front row who knows all the material already, or if your goal is to do undergrad research (a better one), I wouldn't worry so much.
Once something cool does hit you, you'll find building it easier and more fun than any work or learning exercise.
Your main competitor in my eyes is Facebook. The "circles" you promote seem similar to "friend lists," an underemphasized but existant feature on FB. I can publish content to only certain lists with a few clicks. It's kludgy but doable. I manage only one list on Facebook because that's all the granularity of privacy I need. Most people care less than I do, so I don't see a significant need.
Cool design, but the text on the infographic seems off (perhaps it should be actual text and not part of the image). Your about us page is not terribly long yet still wrought with syntax, grammar, and word usage mistakes.
Great game. A little QA: your enemies are speaking a mix of German and English, and the signage is English. When you follow woogley's advice and change the sprites out, make sure exit becomes Ausgang. Some enemies say "fire!" instead of "feur!", and some say "stop!" instead of "halt!" Also, I couldn't restart the game at the game over screen (using c or x). Chrome 10 on OSX.