Summary: Aldon Smith has a lot of potential. As a redshirt freshman, he hit double digits in sacks with 11.5. He might have done it again in 2010 if his season hadn't been interrupted by a broken fibula, though returning quickly from that injury showed toughness that scouts love.
Smith is still learning the game having only played two years in high school and two more in college. Anyone who can rush the passer is going to be coveted in the NFL draft, but there are issues. If he is going to be a 4-3 defensive end as more than a rush specialist, he needs to put on more weight. Teams looking to convert him to outside linebacker in a 3-4 will need to be confident he can learn how to drop into pass coverage, which was not required of him at Missouri. The talent and potential is certainly there.
Player Comparison: Jason Pierre-Paul. This is an easy comparison to draw. Pierre-Paul took the draft process by storm last year as an athletic freak. He was even faster than Smith (4.67 to 4.75 40 at the Combine) and just a little bigger as well. However, athletically they compare well as pass rushers.
Neither player had a ton of production in college with Pierre-Paul having transferred from a junior college and Smith leaving after just two seasons. Both had analysts wondering if they could stand up as a 3-4 outside linebacker prior to the draft as well.