I will be completely honest...i have a 2.6 undergrad GPA and i got in to one of my top choices. Also, my GRE scores are on the low side. However, I have work experience, and numerous internships under my belt, and I got some really strong letters of rec. I was sooooo worried that I wouldn't get in, and honestly I'm still in a little shock that I did. I am not expecting to get into every school I applied to, though.
Also, I think it's important to be very realistic about where you are applying to. For example, I would never waste my time applying to JHU or anything of that caliber.