The only Arsenal penalty that really impressed me was Kolo Toure where he raced in from virtually the center circle and pinged it low into the corner. I think that approach is the best way for a non specialist to take a penalty, just lash it low hard and fast, that way - assuming it's on target - the keeper has to get a fair bit of his body behind it to stop it. I feel a bit sorry for Eduardo, he jittered to try and see which way Doni would go but the Roma keeper didnt commit himself - and he lost all momentum when it came to striking the ball as he'd paused his run up.
Of Roma's takers I thought Montella (right in the corner) Aquilani and Baptista (given his treatment by the crowd) hit good kicks.