Nothing to do but wait.
I sub-mitted two I-485s in NSC in August of 2007, one was based on NIW (PD 09/2006), and still pending. Another was sub-mitted concurrently with EB1 I-140(PD: 08/2007). I did not do anything to re-link PDs of two cases, but I got GC last June.Good Luck!