Mines was approved on Aug/02/2006

in my case:

RD: 09/27/2005 to VSC, then transfered to NSC on on the same day as yours,

I called USCIS three weeks ago,then approved on Aug/02/2006,

In my friend's case, we filed I140 on the same day and transfered to NSC on the same day, but hers was approved on May/30/2006.

It may help if you call USCIS