Fantastic video. It was so nice to see Jeff answering questions earnestly in a semi-formal environment. I love the way he generally composes himself, but sometimes his casually jaded demeanor can make it difficult to gleam genuine information and opinions from his responses. For people interested in video games and the industry, this might be the most informative videos I've ever seen. Well done!
First off, congratulations on your hard work. I went through a similar thing in high school and have managed to keep pretty slim since then -- one of my proudest achievements and it should be one of yours, too! As some have already said here, you're reaching a pretty average weight for men, and at this point you may need to bulk up to begin losing weight again so your body continues to work hard during cardio. That said, if you're an average guy you can probably lose a bit more before needing to bulk up again.
Once again, as people have already said, this can be achieved by "keeping it up". Joining a running or sports club that involves significant cardio (soccer, ultimate frisbee, etc) is an excellent way to make sure that you use your fitness productively and regularly for extended time periods. Progress will be slower than it has been, but I can guarantee you that it will be worth it and feel just as good as it has up to this point. Good luck!
@acidbrandon18: Many excellent suggestions have already been posted but I'll just say don't go into it surprised that she's not annoyed by your existence. Jesus, man, have some fucking dignity. All the girls want your pogo-stick, humanity as a society has kept this from you since birth to give everyone else a chance. Congratulations.