For all pratical purposes David Lee is our franchise player because he's the only one that can energize the entire fan base. Marbury may be the most "talented" player and the most over-paid on the roster but he's not the franchise player.
Lee is the franchise player because he can energize the fans, plays with heart, brings maximum effort and is prepared to play every time his number is called. And most important he isn't LAZY. Now how many guys on the roster can you say have those qualities?