It’s obviously tough because there isn’t a group shot that has everyone. In that case, I believe individual shots would’ve been better–assuming everyone was included. (They did individual shots for season 8 but left out Vincent and included Hilary Swank.)
TeenDramaWhore 
I wonder if Vince Young was in the spot where Luke Perry and Vanessa were photo-shopped in?
No, they created space between Ian and Tiff and removed Vincent from between Tiff and Brian.
See: http://media.photobucket.com/image/beverly%20hills%2090210%20season%209%20cast%20photo/AllezDK/P2P/Rels/90210-beverly-hills-90210-66668_800.png
From what I could find, there’s two other season 9 cast photos but they don’t have Luke or Vanessa, but one includes Tiff and they both have Vincent and Daniel: http://www.vidiot.com/BH90210/images/BH90210-Cast-S9-01.png and http://www.etonline.com/media/photo/2008/03/43831/400_90210cast_080313_getty_51096391.jpg
It’s obviously tough because there isn’t a group shot that has everyone. In that case, I believe individual shots would’ve been better–assuming everyone was included. (They did individual shots for season 8 but left out Vincent and included Hilary Swank.)
For more on the art issues, see: https://teendramawhore.com/2009/12/31/news-roundup-90210-one-tree-hill-gossip-girl-and-the-o-c-5/