i get this too on my 2008 and i am surprised that Jeep hasnt fixed this, it's a safety issue in my opinion especially for a newbie driver i almost read-ended a car at an intersection after this hesitation caused me to depress the gas a little more to get a response then POW!!!! the jeep lurched forward like a top fuel dragster. now that i am aware of this, i drive accordingly. but it is unacceptable for a $18,000 Kia let alone a $40,000 Jeep.
lots of cars have electronic throttles these days. for example the Vette has had this arrangement for several model years now and there is zero hesitation with their system.
2008 Hemi Grand Cherokee Limited 4 x 4, original owner, 29,000 miles