Recived Green Card today. A special case (圖)

My case is different from most of the guys in this forum. I applied for I-140 based on NIW in Jun 2003. Then I went back to China for 3 and half years. I-140 was approved by the end of 2004 (It took longer time at that period and took me $2500). In these three years, I visted states with B2 visa twice and finally decided to get my greencard. 03/05/07 Filed I-485 with 131 by myself (sent to NSC, transfered to TSC) 05/07 FP 06/05/07 filed I-765 (sent to NSC and stayed there ever since) 06/11/07 AP approved 07/25/07 went back to China and came back on 08/08/07 08/10/07-08/13/07 Called service representive continuously for 3 days to get 765 approved 08/15/07 I-765 approved 08/21/07 Received the green card been ordered letter 08/22/07 Received the Welcome Letter 08/25/07 Received green card Spouse case is still pending