I've noticed the last few weeks that challenged calls that appear to be wrong on the field haven't been overturned upstairs.
Take, for example, Percy Harvin's "fumble" against Vanderbilt. The end-zone camera clearly showed him reaching the ball over the goal line for a score. However, the side judge ruled that he fumbled and was recovered by the Commodores.
The call was blown and it took nearly five minutes to make a ruling. Are the replay guys that old and vision-deprived that they can't make a simple call?
Another example was CJ Spiller's "touchdown" against Florida State. With the Seminoles leading, 34-20, Clemson's running back went near the goal line and reached the ball over the pylon. The closest camera angle showed that the ball didn't even go over the pylon. The replay officials looked at it and kept the original call.
If we're going to have instant replay, the review officials must be correct. And if they can't be, a younger viewer might be needed.