Jackson HAS made great strides in his game ... thus, he deserves massive kudos for the improvements in his game. However, with that said, he's still not quite yet at NFL caliber play. Part of the reason why he has so many pass break-ups is that he gets targeted a ton. Opposing Os wouldn't go after him so much unless they saw aspect of his game that were exploitable.
Jackson is certainly having a big of a "break out" season ... however, he certainly would benefit from another season of honing his craft. The ultimate goal of a football player with NFL aspirations is not just to get drafted ... the goal is to "stick." The NFL really doesn't put the effort it once did in player development .... so consequently, it benefits a player to develop as much as possible BEFORE they hit the pros.
The exciting thing about Jackson, in my estimation, is that he's not even close to his plateau (in terms of ability) yet ... so there is still A LOT of room for improvement. Assuming he sticks around next year ... that would mean great things for our secondary!