I doubt Amanda Ripley will have any significance in Defiance. I didn't finish Isolation yet so i have no idea if Defiance could take place after the events of A.I.. If Fox is planning a sequel to Isolation in the future, however, then A. Ripley might be a character no one can touch right now but only to reference and shoe horn for more cash. As it stands, if Defiance takes place before Isolation, Amanda will still have no significance as she hasn't even encountered any xeno's yet. Speaking of Isolation, anyone ever read Alien the illustrated story? I'm guessing the folks who created Isolation didn't as the warning signal was switched off by Dallas in that interpretation. Or maybe they purposely ignored it?