I was told at a few interviews that I didn't need to worry about my stats...that they wouldn't have asked me to do an interview if they didn't think my grades were good enough. If you get an interview, then I think your acceptance is based on how well you do in that interview and they aren't considering your grades as much after that. I did TERRIBLE at my first interview, I was nervous and I didn't have great answers planned out...thus, I didn't get into that school. I practiced my answers to the main questions like "conflict resolution", "leadership", "why OT" and did a ton better and got offers to the rest of the schools I interviewed with. So, if you get an interview, you just have to be confident.
I still have 2 prerequisite to do, like 20hrs of OT observation, and an okay GPA (mid/lower 3's). But the field is getting more competetive, so the more you can do, the better.