I've been bringing tour groups out there off and on for a few years now - in 2006 it was rather active. Since then, less so.
There are two major problems with this place:
1. The atmostphere is conducive to LOTS of false positives. There are some lamps in the windows that tend to look like feminine forms. Plenty of places for light to bounce around and become an "orb." And I've seen TONS of "ghost coming down the stairs" pictures that turned out to be the same thing: the reflection of the photographer's ear.
2 (and this is the big one). most of the stories going around about the place are crap. There was never actually a devil baby, and it certainly isn't buried in the garden next door (there was a building there in 1913, when the rumors went around). There's no native american curse on the grounds (seeing as how Addams won a Nobel Prize for her work there, this would have been one incompetent band of native americans), and no headless ghost that'll follow you home if you don't cross yourself. A major reason that I don't go there much is that some of these stories are bad news - the staff (understandably) wants the house to be remembered for Addams' work, but people tend to treat it as a ghost hunting theme park. I've been trying to talk the other tour guides in the city into stopping spreading around the stories we know are fake, but with varying results. We ended up putting a whole section in the Weird Chicago book on "myths of hull house." Some of the ghost stories that aren't real are pretty harmless, but the devil baby stories need to go. People hear on tours that it's buried in the garden and show up the next day with shovels and bug the staff to let them start digging.
That said, I do have some reasn to think the place is haunted - I've got some GREAT full body apparition shots that I've yet to explain away. Charles Hull very likely held seances there around the time of the civil war. That the place was haunted was sort of a running joke among Jane Addams and the staff. There was also a ghost seen regularly back at the turn of the 20th century at a house where the student center BEHIND hull house now stands. When Addams moved in, the place was right next to an undertaking parlor. Cameras do tend to act funny there; one night I had a group in which not one person could get a shot of one tree. Every time we tried, the cameras would go off or the picture would be messed up.
I also just recently did a blog entry on the reading of Charles Hull's will - it plays like a scene from "Clue." All the relatives gathered in his house (not the haunted one; a long demolished one a few blocks further west) for the opening of the envelope. A bust of Hull presided over the affair. All of the nephews and their wives expected to strike it rich. But everything went to Hull's cousin, who was also his housekeeper.