What are my chances of getting into top colleges? What should I start doing?

Some background details...: I'm going to be a junior next year. Right now, I have a GPA (combined freshman and sophomore year) of 4.27 (3.87 freshman year, 4.67 sophomore year). I am in all honors and AP classes, am in the National Honor Society, the California Scholarship Foundation, my school's Majors Program, Leadership, and have done ballet since I was four (and all through high school). As of right now, I have 287 hours of community service but plan on doing a lot more. I didn't prepare for the PSAT and was in the 91st/92nd percentile for all areas, and have been working my butt off for the SAT which I plan to take two or three times. I'll take the SAT subject tests in probably Spanish, English, and chemistry. Next year I am taking AP Chemistry, AP Environmental Science, AP US History, AP Spanish, Honors American Lit., Honors Pre-Calculus, Kings' Page (the newspaper), and Leadership. Advice, please!