Went tonight. Great movie, packed house with applause at the end. Interstellar was more original, but The Martian was more entertaining. I had read the book, but still was on the edge of my seat.
For the parents out there (very minor spoiler)...
My 12 year old had read the book too, so I took her and at the last minute I took my almost-10 year old too (she is pretty mature and "common sense media" said it was ok for 11 year olds). The horror movie previews before the movie are pretty hairy, so have them stay outside or cover their eyes/ears for that part. The movie itself was perfectly fine for kids if you don't mind a couple f-bombs. Only part that was remotely disturbing to them was a scene where he had to staple his own wound shut towards the beginning, that kinda dragged on a bit too long. Otherwise, they were transfixed the whole movie and loved it.