Previous GPA is important, but not as important as in academic disciplines. A 3.5 or better should be enough — as long as everything else is strong.

GMAT is important. If you can score 700+, you ar ein good shape. Below 650 might be a problem.

Work experience is important. Top schools want 3-5 years of work experience. Working for a prestigious company or an unusual company will help.

Recommendations are important — but will not be the deciding factor in your favor (but a bad one will kill your chances).

Your admissions essays and interview are important. They are important both ways — for example, my interview at Columbia made me realize that it was the last place I wanted to go — while my interview at Duke made me move it up to the top of my list.