"FTW" is internet slang for, "For the win!" and is used especially to express approval or support of something. It is often added as enthusiastic emphasis to the end of a comment, message, or post. Sometimes genuine, but often sarcastic.
After apologizing to Bond, Vesper locks herself in the elevator just before it plunges into the waters below. Bond frantically tries to save her life, but in a final gesture, she kisses Bond's hands as if to clear him of guilt and lets herself drown.