Fabregas is not a natural leader and its easy to see that. He is a role model and someone to look up to but no way a leader. Maybe someone like Vermaelen when he comes back could do a decent job.
A) We're not going to strip Cesc of the captaincy
B) Why is the captain the only one who can shout and be a "leader" - if the Englad captaincy doesn't matter because Ferdinand/Terry will shout and "lead" whether they have the armband or not, why does it matter at Arsenal?
Ceac leads by example - others shout.. I'm sure if players need help on the pitch, he's more than capable of directing them.