it is not as bad as you might have thought.

They will not cancel your PR application in US. Now you are pending with your 485. Since they have made a note in your file, you might have to relinguish Canada PR when your 485 is about to be approved. Don't worry. It is only within the INS officer's authority that your 485 could be denied or approved. The borden INS can't do that.
I had similar case with yours. The borden INS was unhappy with my double PR application and questioned me for a long time. But I came back with AP and got my US GC this June.
If you still have some question, you can send QQH to me. I haven't been here for a long time and haven't posted anything recently. But since your case is so similar to mine, I feel that I am obliged to offer some information, if you desire.

所有跟帖： 

• had u relingquished ur canadian PR before ur GC -虛心請教大家啦- ♂ (13 bytes) () 08/08/2007 postreply 13:59:22

• what happen if Canadian PR approved before filing 485? -DO-PERM- ♂ (0 bytes) () 08/08/2007 postreply 14:07:28