There's a lot of speculation surrounding the college essay and what most colleges are looking for.
I often wonder the same things myself. Do those in admissions want to see riveting personal anecdotes that exemplify strong traits? Do they want to see how the applicant is specifically qualified for the college in question?
What is wanted?
Anyway, I stumbled upon a book that does a good job of explaining all this It's downloadable for free, and even provides a template for writing a good paper. Other parts of the book are quite satirical and funny, but the chapter "For students" hits the nail on the head.
Check it out: Smashwords — **** Ain't Perfect: Lessons in Real-World Living — A book by E Ballz