I've been using Humira for 12 weeks for Crohn's disease as well. The greatest benefit for me was that I've been able to come off of Prednisone (which I was on for a year and gained 100 pounds because of it). The only difference I see taking Humira is that I haven't developed any fistulas which I did within weeks of coming Prednisone previously with no other meds on board.
The problem I have with Humira is that I have severe swelling in my knees, ankles and feet and my family doctor has recommended that I stop Humira injections because she can't treat the swelling without risking heart problems. I have also developed multiple infections that I cannot get rid of.
I have an MRI scheduled in February which is supposed to see if the Humira was having any effect. I do not want to go back on steriods in the interim. As always seems I am stuck between a rock and a hard place.