Well, if you're a Cylon, you can die, download and be resurrected, as long as there's a resurrection ship in the vicinity.
Moore says the 12th Cylon is not a major character:Quote from article,
http://seattlepi.nwsource.com/tvguide/357752_tvgif4.html
Eleven Cylons now have been revealed, so who is the 12th and final Cylon? Contrary to fan speculation, Moore swears it isn’t one of the show’s primary humans. Not Starbuck or President Roslin. Not Admiral Adama (Edward James Olmos) or his son, Lee (Jamie Bamber). Or even the ever-dubious, Cylon-shagging Gaius Baltar (James Callis). “Even if you guess correctly, it’s still just a guess,” Moore says. “There’s no way anyone can figure it out without knowing exactly where we’re going with the final season.”
Since much of that remains to be filmed, the cast is clueless. “We’re going along for the ride, just like the fans,” Trucco says. “We don’t even know where the four new Cylons fall in Cylon chronology. Are we predecessors? Or did we come afterward? Are we divine?”
Adds Douglas: “So far, in scripts, there are no multiple copies of us, unlike with the other Cylons, so maybe we’re one-offs. Does that mean we can die?”
And what about the humans’ quest for Earth? Moore promises that they will arrive there — uh, here — before the series wraps up. But what will they find? Dinosaurs? Ancient Greeks? George W. Bush? “We’ve never revealed our timeframe, and that’s been one of the key questions from the very beginning,” Moore says. “What is the connection between us and the humans of BSG?"
Douglas concludes, “All I know is that everything better track when all is finally revealed, because there’s nothing like a sci-fi fan scorned!”
In the BSG Last Supper pic to promote season 4 Moore says there is an empty chair between Saul Tigh and Lee Adama for the 12 th Cylon. This means the other 12 people at the table are not the 12th Cylon.
http://images.search.yahoo.com/imag...441803/&p=bsg+last+supper&type=jpeg&no=3&tt=5
http://www.ew.com/ew/article/0,,20169703,00.html