Thought this might be of interest.. was looking for something else and I was reading the CSI Wikiedia which has just recently changed...
It now lists Warrick as Past Main Characters and I Quote " As a result, in the Season 8 finale, the undersheriff shoots Warrick in the neck and chest while he is sitting in his car, and then leaves him to die from his wounds. So far, Warrick is among three main cast characters to be killed off the franchise. (The first being Tim Speedle of CSI: Miami and the second being Aiden Burn of CSI: NY). " Unquote.
Also.. I want to say that I didn't watch his final episode until this evening and I was to say that I thought it was horrific. By that I mean, I was speechless... I knew it was coming yes, but with the music and the scene with the team just before it. I know the show can be graphic and don't get me wrong I am a collector of horror movies... I go to horror conventions, but this was so heartbreaking. I just said out loud... quite loudly... That was sooo horrifying. I didn't want to see him go like that. It was terrible.