I don't think the Chiefs are giving up on him yet either. I know it looked like they drafted 2 DE's this year (Allen Bailey and Gabe Miller) but later read that Pioli said Miller is going to be a Developmental OLB and Special Teams contributor.
Bailey looks like a sign that we aren't re-signing Shaun Smith and will rotate with Jackson and or course Gilberry will rotate with Dorsey.
If you think about Hali..... He really didn't come on until his 3rd year, and last year (his 4th) was when he really became a stud. This year will be Jacksons 3rd year and he showed flashes last year after his injury.