We finally have pictures of J-11BS coming out. I just got these yesterday and it's quite exciting actually. If you look at the cockpit, you can see the tandem seating like that of Su-30mkk. A lot of people have said that this is supposed to be Chinese version of Su-30. I'd have to look at them side by side, but my guess is that it would either be same in dimension to Su-30 or Su-27ubk (likely the former). You can see that it has black nose and black engine nozzle just like the photos we got in early 2007 of J-11B testing at CFTE. I believe the serial number for this is 532 compared to 52x for the J-11Bs.
Back then, people thought that black engine nozzle and nose indicate the usage of domestic engine (WS-10A) and radar. I think it's good to compare them a little more closely. The pictures below do a good job of showing the petals on the engine nozzles of Ws-10A and AL-31 (first one is WS-10A and second is AL-31). If you look at the original picture, the petals on the J-11BS does look like that of WS-10A. You see that the petals are one on top of the next rather than the pattern seen on AL-31FN in the second photo. I will stop there, since I don't think I'm qualified to comment on any more than this.
The other interesting part is that this is 532, so this is pretty much the second J-11BS sent to CFTE for testing. We received news a while ago, that one of the J-11BS crashed in flight testing, that probably was 531. Regardless, it seems like SAC is stuck working on different variants of flankers. J-11BS is basically China's version of F-15E, a long range strike aircraft with good A2A combat capabilities. It is the heavy, multi-role aircraft that PLAAF have been waiting for a while for. The next plane we are expected to see from SAC is J-11BJ, aka the naval flanker.