Aerobraking seems like a natural for a gas giant like Jupiter but in this case it is not practical. To do aerobraking, the spacecraft comes in from heliocentric orbit, skims the upper atmosphere to bleed off kinetic energy and then does a periapsis raising burn at apoapsis after leaving the atmosphere. Without the periapsis raising burn, the spacecraft will reenter the atmosphere on the first orbit and burnup. That periapsis raising burn is the "gotcha" with Jupiter aerocapture. If you do the numbers, you find that it takes less of a burn (delta-V) to do a higher altitude Jupiter orbit injection burn without aerocapture (as used with the Galileo orbiter) than the burn required with aerocapture to raise the periapsis. This is because Jupiter's gravitational well is so deep (you have to get too deep into the well to use the atmosphere). Also there is the additional problem of Jupiter's extreme radiation belts.

Aerocapture at Neptune is the correct (and in fact only practical) way of going into a Triton transfer orbit. However the aeroshell heat soak experienced during Neptune aerocapture is enormous (greater than the heat soak experienced by the Galileo Probe). Triton is of high scientific value (a Kuiper belt object with a tenuous atmosphere) so coming up with a Neptune aerocapture technology offers a high payback.

Gary