I am seeing the same thing.
I have a group set up for my phone contacts, When I create a contact on my RAZR (Verizon M version) it does transfer via iSync to my address book but does not show up in the group, only in "All". If I find it and drag it to the group it is ok, but if I delete from the group it doesn't delete from the phone. I have to completely delete the contact to have it removed from the phone.
Any ideas, is this a bug that the phone doesn't seem to be connected to the group correctly?