JCP appears to be a disaster that continues to get worse. TGT was a bust. HLF bet could turn against Ackman as well. His GGP investment was great, but that was sourced by one of his junior guys, not him (rumor has it the guy got $20m at ~26/7). Could we be seeing Ackman's status unravel? Will his investors begin to leave?
I've personally heard of how he deals with management teams and boards and find the stories repulsive. People on the buyside typically don't like him very much and not because they're jealous. I'd imagine that this behavior doesn't go unpunished forever.