Isn't Xapo already a Bitcoin Bank? I've heard they will protect your coins in some cold storage computers shielded inside an underground bunker with security cameras and armed guards, sounds pretty cool.
if you think about it any exchange can be considered kind like a bank, if you hold money there, many are just less secure than others
banks are welcome only if they can offer a 100% secure investments with bitcoin..i'm talking about interest like with fiat
but this will surely bring, the already little portion of the bitcoin anonimity, down