There used to be. It mysteriously disappeared about 2 weeks ago. I think the guy that ran it started to get scared because there was so much management bashing going on. If you work for Pinnacle and have your ALPA number you can always go to the message board on ALPA's website.
Does it matter? All they have to do is sue you and then you have to pay a lawyer to defend you. Meanwhile, they throw 5 or more lawyers at you. Drown your lawyer in paper work (that you have to pay for) and essentially force you to settle out of court simply from a lack of funds.
PS...there is a board on ezboards.com that is primarily a Mesaba Board but Pinnacle pilots chat there too.