Well, i am truly amazed that such a question can even be asked. Every club has a captain, and this very captain often embodies the heart and soul of the team, or at least the one most respected by the coach, the players and the fans. Or the captain could even be the one that has stayed the longest at the club.
It is no surprise then, to note that Javier Zanetti fits all 3 of the above-mentioned descriptions. I don't think there is even a need to consider a new captain as long as Il Capitano is still around. Back in 2000, there was a debate about whether Ronaldo should be the captain; i staunchly refused to accept a proposal to see Ronaldo as a captain or even as a vice-captain. Why? Because he doesn't deserve it.
Fast forward to 2004, and again i see this same question! Really, what must Javier Zanetti do to gain the utmost respect of EVERY Interista once and for all? He has been the most dedicated player we have on our ranks. He goes into every game wearing the colors of the jersey on his heart, and even if he has a bad day, you can see that he tried his level best. Il Capitano is a model professional, a true fan of the club and our longest serving player. If those are not good enough requirements to be our club's captain without a shadow of a doubt, then how about this - Javier Zanetti loves this club and the club absolutely loves him. IMO, the sum of all descriptions is enough to ensure that Il Capitano remain as that until the day he retires.
After all, nobody is more deserving of the captaincy than the one who has given his all for the club.
Ciao,
Tim