I think the only reason he's so intent on staying is because Inter were also his childhood club... anyone else would probably want to leave. He's far from a world class player, but I'd rather give the captaincy to someone who's been loyal to the club for a while than to someone who's just arrived. But I guess since Vidic has the experience factor and is a proven leader, realistically he is a better candidate.
How much would he realistically play if he went to Juve anyway?