According to
this thread:
Giant along with Jamis was removed by performance. Performance is trying to open a ton of new stores and they overlap territories with existing dealers so Giant would not open all of them, because of this Performance is becoming Pacific only, Mongoose, Schwinn, GT.
Specialized made the decision to pull out of supergo because to many of their IBD's were upset about them being there. I got the word from Specialized direct, so I'm positive it is true. It will probably be reported to the public on Monday.
Take that for what it's worth.